JP2001354010A - Pneumatic tire - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress any partial wear generated on a flat portion of a shoulder of a pneumatic tire fitted to a vehicle having a camber angle. SOLUTION: The shearing force on the braking side of a shoulder block 26 is reduced to suppress any partial wear by setting the rigidity of the tire in the circumferential direction of the shoulder block 26 on the inner side when fitted to the vehicle set to be a negative camber to be larger than the rigidity of the tire in the circumference direction of a shoulder block 30.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pneumatic tire used in a state of being inclined with respect to a road surface, and more particularly to a pneumatic tire capable of suppressing uneven wear, in particular, partial wear of a shoulder portion.

[0002]

2. Description of the Related Art Conventionally, in a tire pattern in which the front and rear sides of a tire are designated asymmetrically with respect to the tire equatorial plane (front and rear asymmetrical patterns with respect to the tire equatorial plane), the outside of the tire when turning on a dry road surface. While the block stiffness was set large in consideration of the steering stability, the negative was set large on the inside of the mounting in consideration of the steering stability when wet.

[0003]

However, the use of such a pattern reduces the rigidity of the block inside the mounting, so that it is used especially when mounted on a vehicle with a negative camber setting. In many cases, the inner shoulder portion has a disadvantage that the amount of wear is larger than in other regions, and uneven wear called heel-and-to wear occurs.

[0004] Further, since the inner side of the mounting is hardly noticeable, if the belt is continuously used without being noticed, there is a possibility that the belt layer may be worn and a burst may occur.

The present invention has been made in consideration of the above-described facts, and a first object of the present invention is to provide a pneumatic tire capable of suppressing uneven wear of a shoulder portion.

A second object is to maintain steering stability while suppressing uneven wear.

[0007]

According to various experiments by the inventor, a detailed observation of the tread behavior of the contact portion of the tire with the negative camber attached shows that when the vehicle is mounted on the vehicle compared to when the camber is not attached. It was found that the shear force on the braking side (in the direction opposite to the traveling direction of the vehicle) increased in the inside portion of the vehicle, and decreased on the outside portion when the vehicle was mounted.

The lateral grooves (hereinafter referred to as lugs) extending in the tire width direction arranged in the pattern contract and stick in the tire circumferential direction at the time of contact with the ground. In contrast, when there is no tread, more treads enter the unit road surface length of the ground contact portion (in the tire circumferential direction).

As a result, the rolling radius becomes smaller in the portion where the lug is increased, and the shearing force on the braking side is relatively increased with respect to the other regions. It was found that the force increased.

That is, if there is a difference in diameter between the tires, the tire rolls on the road surface mainly on the large-radius portion that is in contact with the ground, so that the small-radius portion is relatively moved in the vehicle traveling direction relative to the large-radius portion. , Ie, a shear force is applied to the braking side.

[0011] The shear force causes the wear of the land to progress.

The groove shrinkage of the lug is affected not only by the presence or absence of the lug component but also by the magnitude of the land rigidity of the land portion located in the tire circumferential direction of the lug component even if the lug component is the same.

Therefore, in order to improve the point that the shear force on the braking side inside the mounting is increased due to the attachment of the negative camber, the land portion rigidity (in the tire circumferential direction) of the shoulder portion inside the mounting is increased. Conversely, by setting the land rigidity of the shoulder part on the outside of the mounting to be small,
It has been found that it is possible to suppress the occurrence of uneven wear on the inside of the mounting caused by mounting and using the vehicle with a negative camber.

[0014] The invention described in claim 1 has been made in view of the above facts, and includes a plurality of circumferential grooves extending substantially in the tire circumferential direction, and substantially a circumferential groove extending substantially in the tire axial direction. A plurality of land portions separated by a plurality of extending lateral grooves are formed on the tread, and when mounted on a vehicle set with a negative camber, the pneumatic tire has a designated front and rear mounting on the vehicle. the tire circumferential rigidity of the land portion of the shoulder portion to be outwardly G _os, the tire circumferential rigidity of the land portion of the shoulder portion serving as a vehicle width direction inside when the G _iS, it is G _os <G _is It is characterized by.

Next, the operation of the pneumatic tire according to the first aspect will be described.

In the pneumatic tire according to the first aspect, when the negative camber is mounted on the vehicle, the tire circumferential rigidity Gis of the land portion of the shoulder portion which is on the inner side in the vehicle width direction _{is changed} to the land portion of the shoulder portion which is on the outer side in the vehicle width direction. Is set to be larger than the tire circumferential rigidity _Gos , so that the shearing force on the braking side of the land portion of the shoulder portion on the inside in the vehicle width direction can be reduced, and the land portion of the shoulder portion on the vehicle width direction inside can be reduced. The uneven wear that occurs can be suppressed.

Here, the rigidity of the land portion is calculated by the equation (1) shown in FIG.
It is assumed that

Note that the rigidity of a tread pattern having a pitch variation is an average value of each pitch.

The term "negative camber" as used herein includes not only the case where the tire is inclined inward while the vehicle is stationary, but also the case where the tire is dynamic (during use). For example, when the camber angle is 0 ° at rest
Or, even if the camber angle is negative when the vehicle is in use, the camber angle is regarded as a negative camber.

The invention according to claim 2 is the invention according to claim 1.
In the pneumatic tire, the outer side in the vehicle width direction
The tire circumferential length of the land part of the shoulder part is L_os, The car
The circumferential direction of the tire on the land part of the shoulder part on the inside in both width directions
Length is L_isAnd L _os<L_isIs characterized by
And

Next, the operation of the pneumatic tire according to claim 2 will be described.

When the negative camber is mounted on the vehicle, the tire circumferential length L _is of the land portion of the shoulder portion which is on the inner side in the vehicle width direction _{is calculated} from the tire circumferential length L _os of the land portion of the shoulder portion which _is on the outer side in the vehicle width direction. The tire circumferential rigidity G _is of the land portion of the shoulder portion which is on the inner side in the vehicle width direction when the vehicle is mounted with the negative camber is larger than the tire circumferential rigidity G _os of the land portion of the shoulder portion which _is on the outer side in the vehicle width direction. Can be set large.

According to a third aspect of the present invention, there is provided the pneumatic tire according to the first or second aspect, wherein the shoulder portion on the outer side in the vehicle width direction has a land portion in the tire circumferential direction. It is characterized in that a reinforcing portion is provided.

Next, the operation of the pneumatic tire according to claim 3 will be described.

In the pneumatic tire according to the third aspect, the land portion circumferential reinforcing portion increases the tire circumferential rigidity of the land portion.

According to a fourth aspect of the present invention, in the pneumatic tire according to any one of the first to third aspects,
When the rigidity in the tire width direction of the land portion of the shoulder portion on the outer side in the vehicle width direction is G _oh , and the rigidity in the tire width direction of the land portion of the shoulder portion on the inner side in the vehicle width direction is G _ih , G
_oh > G _ih .

Next, the operation of the pneumatic tire according to claim 4 will be described.

If the distribution of the land rigidity in the circumferential direction is changed as in claim 1 by simply considering only the uneven wear performance, the distribution of the land rigidity in the tire width direction also changes, and the land portion of the shoulder portion on the outer side of mounting is changed. The cornering power is reduced because the tire widthwise rigidity _Goh is reduced (because the load on the outer part of the tread is increased during cornering), and satisfactory steering stability is achieved despite the asymmetrical pattern. You may not be able to get it.
At the same time, the negative ratio inside the mounting decreases,
In particular, there is a case where the wet performance at the time of going straight is reduced.

If the rigidity G _ih in the tire width direction at the land portion of the shoulder portion on the inner side in the vehicle width direction is made smaller than the rigidity _{Goh in} the tire portion in the land portion of the shoulder portion on the outer side in the vehicle width direction, by securing the negative ratio required for wet performance (particularly during straight) to narrow the tire width direction dimension while increasing the tire circumferential rigidity G _iS of the land portion of the shoulder portion comprised of an inner, a rolling radius of the inner side It can be made relatively large, and at the same time, a decrease in wet performance can be suppressed.

Furthermore, by increasing the tire width direction rigidity G _oh of the land portion of the shoulder portion of the mounting outside while reducing the tire circumferential rigidity G _os of the land portion of the shoulder portion serving as a vehicle width direction outside, mounted outside This is more preferable because the rolling radius of the tire can be made relatively small, and at the same time, a decrease in cornering power can be suppressed.

The invention according to claim 5 is the invention according to claim 4.
In the pneumatic tire, the outer side in the vehicle width direction
The length in the tire width direction of the land part of the shoulder part is L_oh, The car
Tire width direction of the land part of the shoulder part which is inside on both width directions
Length is L_ihAnd L _oh> L_ihIs characterized by
And

Next, the operation of the pneumatic tire according to claim 5 will be described.

When the negative camber is mounted on the vehicle, the length L _ih of the land portion of the shoulder portion on the inner side in the vehicle width direction is larger than the length L _oh of the land portion of the shoulder portion on the outer side in the vehicle width direction. Since it is set to be small, the tire width direction rigidity G _ih of the shoulder land portion which becomes the vehicle width direction inner side when the negative camber is mounted on the vehicle is changed to the tire width direction rigidity G _{oh of the} shoulder portion which becomes the vehicle width direction outer side.
Can be set smaller.

According to a sixth aspect of the present invention, there is provided the pneumatic tire according to the fourth or fifth aspect, wherein the shoulder portion on the outer side in the vehicle width direction has a land portion in the tire width direction. It is characterized in that a reinforcing portion is provided.

In the pneumatic tire according to the sixth aspect, the land portion axial reinforcing portion provided on the tire axial side surface increases the rigidity of the land portion in the tire axial direction.

According to the seventh aspect of the present invention, the tire circumference
Circumferential grooves extending along the
Divided by a plurality of lateral grooves extending along the axial direction
Lands are formed on the tread and
Pneumatic tires with specified front and back mounting
When mounted on a vehicle set to live camber, the vehicle
Tire circumferential stiffness in the shoulder area on the outer side in the width direction
G_os, Of the shoulder part on the inner side in the vehicle width direction
Tire circumferential rigidity is G_isAnd when G_os> G_isIn
It is characterized by that.

Next, the operation of the pneumatic tire according to claim 7 will be described.

In the pneumatic tire according to the seventh aspect, when the positive camber is mounted on the vehicle, the tire circumferential rigidity _Gos of the shoulder portion on the outer side in the vehicle width direction is changed to the land portion of the shoulder portion on the inner side in the vehicle width direction. _Is set larger than the tire circumferential rigidity Gis, it is possible to reduce the braking force on the braking side of the land portion of the shoulder portion on the outside in the vehicle width direction. The uneven wear that occurs can be suppressed.

The term "positive camber" used herein includes not only the case where the tire is tilted outward while the vehicle is stationary, but also the case where the tire is dynamic (during use). For example, if the camber angle is 0 ° or minus when stationary, a camber angle that becomes plus when used is a positive camber.

[0040]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS [First Embodiment] A first embodiment of a pneumatic tire according to the present invention will be described below in detail with reference to the drawings.

The tread 12 of the pneumatic tire 10 of the present embodiment has a circumferential groove 14, a circumferential groove 16, a circumferential groove 18, a circumferential groove 18 extending along the tire circumferential direction (the direction of arrow A and the direction of arrow B). A plurality of lateral grooves 20 formed between the groove 14 and the circumferential groove 18 and extending in the tire width direction (arrow L direction and arrow R direction), a lateral groove 22 extending from the circumferential direction 18 in the arrow R direction, and traversing the tread 12. A lateral groove 24 is formed.

The shoulder block 26 defined by the lateral groove 24 and the circumferential groove 14 has a rectangular shape elongated in the tire circumferential direction, and has a central block 28 formed between the circumferential groove 14 and the circumferential groove 18 and a circumferential block. The shoulder block 30 formed on the arrow R direction side of the groove 18 is a rectangle that is long in the tire width direction.

The pneumatic tire 10 is a tire having a directional characteristic such that the direction of the arrow R points toward the outside of the vehicle (the direction of the arrow L points toward the inside of the vehicle) with respect to the vehicle provided with the negative camber. is there.

The tire circumferential dimension L _is of the shoulder block 26 on the inner side of the mounting is larger than the tire circumferential direction _{Los of the} shoulder block 30 on the outer side of the mounting. The dimension W _{is the} shoulder block 3 on the outside of the mounting
0 is set smaller than the tire width direction dimension W _os .

In this embodiment, the circumferential grooves 1
4, circumferential groove 16, circumferential groove 18, lateral groove 20, lateral groove 22
The groove depths of the lateral grooves 24 are all the same. (Operation) When the negative camber is mounted on the vehicle, the shoulder block 26 which _is on the inner side in the vehicle width direction and the tire circumferential length Lis _{is the} shoulder block 30 which _is on the outer side in the vehicle width direction.
Since the larger the tire circumferential direction length L _os, the shoulder blocks 26 tire circumferential rigidity G _IS is larger than the shoulder blocks 30 tire circumferential rigidity G _os, to reduce the shearing force of the brake side of the shoulder block 26 Therefore, uneven wear generated on the shoulder block 26 can be suppressed.

Further, the length L _ih in the tire width direction of the shoulder block 26 on the inner side in the vehicle width direction is set smaller than the length L _oh in the tire width direction of the shoulder block 30 on the outer side in the vehicle width direction. The tire circumferential rigidity G _{is of the} shoulder block 26 on the inner side is the tire circumferential rigidity G of the shoulder block 30 on the outer side in the vehicle width direction.
greater than _os, by securing a negative ratio required for wet performance (particularly during straight) to narrow the tire width direction dimension while increasing the tire circumferential rigidity G _IS of the shoulder block 26, mounted inside the rolling radii Can be relatively increased, and at the same time, a decrease in wet performance can be suppressed.

Further, by increasing the tire width direction rigidity _Goh of the shoulder block 30 while reducing the tire circumferential direction rigidity _Gos of the shoulder block 30 located on the outer side in the vehicle width direction, the rolling radius on the outer side of the mounting is relatively reduced. The size can be reduced, and at the same time, a decrease in cornering power can be suppressed. Second Embodiment A pneumatic tire according to a second embodiment of the present invention will be described below in detail with reference to the drawings. In addition,
The same components as those in the first embodiment are denoted by the same reference numerals,
The description is omitted.

As shown in FIG. 2, a pneumatic tire 40 according to the present embodiment is a modification of the pneumatic tire 10 according to the first embodiment, and has a lateral groove 42 formed in the shoulder block 26 at a central portion in the tire circumferential direction. And shoulder block 26
Is divided into two in the tire circumferential direction. This lateral groove 42
The tire circumferential length of the small block 26A divided by
Because it is longer than the circumferential length of the shoulder block 30,
The circumferential rigidity of the small block 26A in the tire circumferential direction is larger than the rigidity of the shoulder block 30 in the tire circumferential direction, and in this embodiment, uneven wear generated on the shoulder block 26 can be suppressed. [Third Embodiment] Hereinafter, a third embodiment of the pneumatic tire of the present invention will be described in detail with reference to the drawings. In addition,
The same reference numerals are given to the same components as those in the above-described embodiment, and the description thereof will be omitted.

As shown in FIG. 3, a pneumatic tire 50 according to the present embodiment is a modification of the pneumatic tire 10 according to the first embodiment, and has a narrow peripheral portion at the center of the shoulder block 26 in the tire width direction. The direction groove 52 is formed, and the shoulder block 26 is divided into two in the tire width direction.

The circumferential length of the small block 26B divided by the circumferential groove 52 is the same as that of the shoulder block 30.
, The rigidity in the tire circumferential direction of the small block 26 </ b> B is greater than the rigidity in the tire circumferential direction of the shoulder block 30, and also in this embodiment, uneven wear generated on the shoulder block 26 can be suppressed.

The shoulder block 26 on the inner side of the mounting
Since the circumferential groove 52 is provided, drainage performance is improved, and wet performance during straight traveling can be improved. [Fourth Embodiment] Hereinafter, a fourth embodiment of the pneumatic tire of the present invention will be described in detail with reference to the drawings. In addition,
The same reference numerals are given to the same components as those in the above-described embodiment, and the description thereof will be omitted.

The tread 12 of the pneumatic tire 60 of the present embodiment has a circumferential groove 62, a circumferential groove 64, a circumferential groove 66, a tread 12 extending along the tire circumferential direction (the direction of arrow A and the direction of arrow B). Is formed.

The shoulder block 70 located on the side of the circumferential groove 62 in the direction of the arrow L and the shoulder block 72 located on the side of the circumferential groove 66 in the direction of the arrow R are both rectangular and long in the tire width direction. Is formed.

The central block 74 formed between the circumferential groove 62 and the circumferential groove 66 has a rectangular shape longer in the tire width direction, but has a dimension in the tire width direction larger than that of the shoulder blocks 70 and 72. It is set short.

Although the depths (maximum values) of the circumferential grooves 62, 64 and 66 are the same, the circumferential grooves 6
In 6, a raised portion 76 is provided at a portion between the central block 74 and the shoulder block 72 and is formed shallower than other portions.

The groove depth (maximum value) of the lateral groove 68 is the same as the groove depth (maximum value) of the circumferential groove 62, the circumferential groove 64, and the circumferential groove 66. However, the shoulder block 70 and the shoulder A raised portion 78 is provided between the block 70 and the lower portion, and is formed shallower than other portions.

The pneumatic tire 60 is also a directional tire with respect to a vehicle provided with a negative camber such that the direction of the arrow R points toward the outside of the vehicle (the direction of the arrow L points toward the inside). is there. (Operation) In the present embodiment, when the negative camber is mounted on the vehicle, the shoulder block 70 that is located on the inner side in the vehicle width direction is used.
Since the bottom raising portion 78 is provided in the tire circumferential direction, the rigidity in the tire circumferential direction is larger than that of the shoulder block 72 on the vehicle width direction outside where the bottom raising portion 78 is not provided in the tire circumferential direction. The shearing force can be reduced, and uneven wear generated on the shoulder block 70 can be suppressed.

Further, since the raised portion 76 is provided in the tire width direction of the shoulder block 72 on the outer side in the vehicle width direction, the rigidity of the shoulder block 72 in the tire width direction is increased, and a decrease in cornering power can be suppressed. [Fifth Embodiment] Hereinafter, a fifth embodiment of the pneumatic tire of the present invention will be described in detail with reference to the drawings. In addition,
The same reference numerals are given to the same components as those in the above-described embodiment, and the description thereof will be omitted.

The pneumatic tire 80 of the present embodiment is
This is a modification of the pneumatic tire 60 of the embodiment, in which a shoulder block 82 long in the tire circumferential direction is formed on the side of the circumferential groove 62 in the direction of the arrow R.

A short lateral groove 84 is formed in the shoulder block 82 so as not to divide the shoulder block 82 in the tire circumferential direction.

The pneumatic tire 6 of the fourth embodiment
The raised portion 76 and the raised portion 78 provided at 0 are not provided. (Operation) In the present embodiment, when the negative camber is mounted on the vehicle, the shoulder block 82 which is located inside in the vehicle width direction is used.
However, the rigidity in the tire circumferential direction is greater than that of the shoulder block 72 which is located on the outer side in the vehicle width direction. Therefore, the shearing force on the braking side of the shoulder block 82 can be reduced, and uneven wear generated on the shoulder block 82 can be suppressed. it can. [Sixth Embodiment] Hereinafter, a sixth embodiment of the pneumatic tire of the present invention will be described in detail with reference to the drawings. In addition,
The same reference numerals are given to the same components as those in the above-described embodiment, and the description thereof will be omitted.

The pneumatic tire 90 of the present embodiment is
It is a modification of the pneumatic tire 80 of the embodiment.

The shoulder block 82 of this embodiment has no lateral groove 84 formed therein. The circumferential groove 66
The shoulder block 94 is defined on the side of the arrow L by a lateral groove 92 and has a circumferential dimension shorter than the central block 74 and the shoulder block 72 of the fifth embodiment described above. Have been. (Operation) In the present embodiment, when the negative camber is mounted on the vehicle, the shoulder block 82 which is located inside in the vehicle width direction is used.
However, since the rigidity in the tire circumferential direction is larger than that of the shoulder block 94 which is located on the outer side in the vehicle width direction, the shearing force on the braking side of the shoulder block 82 can be reduced, and uneven wear generated on the shoulder block 82 can be suppressed. it can.

Note that the shoulder block 8 of the present embodiment is
2 is different from the fifth embodiment in that the lateral groove 84 is not formed, so that the tire circumferential rigidity is further increased, and the uneven wear characteristics are further improved than the fifth embodiment. . [Other Embodiments] In the above embodiment, an example in which the vehicle is mounted on a vehicle set to a negative camber has been described. However, in the case of a pneumatic tire mounted to a vehicle set to a positive camber, the circumferential rigidity is low. A high shoulder block is placed outside the mounting, and a shoulder block with low circumferential rigidity is mounted inside the mounting. Thereby, uneven wear generated in the shoulder block outside the mounting can be suppressed. In consideration of cornering, it is preferable that the rigidity in the tire width direction of the shoulder block on the outer side of the mounting is higher than the rigidity in the tire width direction of the shoulder block on the inner side of the mounting.

In the above embodiment, the shoulder block and the central block are rectangular, but the shape of these blocks may be other shapes (diamond, trapezoid, polygon, etc.).

The circumferential groove may be slightly inclined with respect to the tire circumferential direction, and the lateral groove may be slightly inclined with respect to the tire width direction. (Test Examples) In order to confirm the effects of the present invention, two types of pneumatic tires having the pattern of the conventional example and six types of pneumatic tires of the example to which the present invention was applied were prototyped and subjected to a wear test to perform uneven wear. In addition to examining the state of occurrence, cornering power and hydroplaning occurrence speed were examined. Example 1 A tire according to the first embodiment. Example 2: Tire of the second embodiment. Example 3: A tire according to the third embodiment. Example 4: The tire according to the fourth embodiment. Example 5: Tire of the fifth embodiment. Example 6: The tire according to the sixth embodiment. Conventional example 1: a left-right asymmetric pattern (the tire is a symmetrical pattern with respect to the tire equatorial plane CL with respect to the tire of the sixth embodiment; see FIG. 7). Conventional example 2: a left-right symmetric pattern (a tire having the same pattern as the tire of the fourth embodiment and having no raised portion; see FIG. 8).

The tire size of each tire was 225.
/ 50R16, and the block dimensions are as described in Table 1 below.

The abrasion test was performed by mounting the test tire on a 7.5 J rim at an internal pressure of 230 KPa and mounting the tire on an actual vehicle. The test conditions are as follows.・ Vehicle: FR passenger car ・ Mounting position: 4 wheels ・ Front wheel load: 5.10KN ・ Front camber angle: -2 ° ・ Rear wheel load: 3.92KN ・ Equivalent to two passengers ・ Speed: 0 to 200km / h ・ Distance : 10000 km The evaluation is based on the difference in the amount of wear between the outer shoulder block and the inner shoulder block.
It was represented by an index value of 0. The numerical value indicates that the larger the value is for convenience, the smaller the difference in the amount of wear is, and the less uneven wear is, the better. Note that an index of up to 98 is a level that is practically acceptable. The results are as shown in Table 1 below.

The cornering power was measured with a tire tester.

The evaluation was expressed by an index with the tire of Conventional Example 1 taken as 100. The numerical value indicates that the larger the value is, the larger the cornering power is, and the better. Result is,
It is as shown in Table 1 below.

The hydroplaning generation speed was determined by assembling the test tire on a 7.5 J rim at an internal pressure of 230 KPa.
The vehicle was mounted on an actual car and traveled straight on a wet road surface.
The test conditions are as follows.・ Vehicle: FR passenger car ・ Mounting position: 4 wheels ・ Front wheel load: 5.10KN ・ Front camber angle: -2 ° ・ Rear wheel load: 3.92KN ・ Equivalent to 2 passengers ・ Water depth: 10mm It was represented by an index with the hydroplaning generation speed of the tire being 100. The numerical values indicate that the larger the value is, the higher the hydroplaning generation speed is, and the better the wet performance is. The results are as shown in Table 1 below.

[0072]

[Table 1]

[0073]

As described above, the pneumatic tire according to the first aspect has the above-described structure, so that when the pneumatic tire is mounted on a vehicle set with a negative camber and used, the shoulder portion on the inner side of the mounting is used. It has an excellent effect that uneven wear occurring on the land can be suppressed without deteriorating the maneuverability.

Since the pneumatic tire according to the fourth aspect has the above-described configuration, the pneumatic tire has an excellent effect that a decrease in wet performance and a decrease in cornering power can be suppressed.

In addition, since the pneumatic tire according to claim 7 is configured as described above, when the pneumatic tire is used by being mounted on a vehicle set as a positive camber, uneven wear generated on the land portion of the shoulder portion outside the mounting is used. Can be suppressed without deteriorating the maneuverability.

[Brief description of the drawings]

FIG. 1 is a plan view of a tread of a pneumatic tire according to a first embodiment.

FIG. 2 is a plan view of a tread of a pneumatic tire according to a second embodiment.

FIG. 3 is a plan view of a tread of a pneumatic tire according to a third embodiment.

FIG. 4 is a plan view of a tread of a pneumatic tire according to a fourth embodiment.

FIG. 5 is a plan view of a tread of a pneumatic tire according to a fifth embodiment.

FIG. 6 is a plan view of a tread of a pneumatic tire according to a sixth embodiment.

FIG. 7 is a plan view of a tread of a pneumatic tire according to Conventional Example 1.

FIG. 8 is a plan view of a tread of a pneumatic tire according to Conventional Example 2.

FIG. 9 is a perspective view of a land part and a calculation formula for explaining a method of calculating the rigidity of the land part.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Pneumatic tire 12 Tread 14 Circumferential groove 16 Circumferential groove 18 Circumferential groove 20 Lateral groove (lateral groove) 22 Lateral groove (lateral groove) 24 Lateral groove (lateral groove) 26 Shoulder block (land portion) 28 Central block ( Land portion) 30 Shoulder block (land portion) 40 Pneumatic tire 42 Lateral groove (lateral groove) 50 Pneumatic tire 52 Circumferential groove 60 Pneumatic tire 62 Circumferential groove 64 Circumferential groove 66 Circumferential groove 68 Lateral groove (lateral direction) Groove) 70 Shoulder block (land portion) 72 Shoulder block (land portion) 74 Central block (land portion) 76 Bottom raised portion 78 Bottom raised portion 80 Pneumatic tire 82 Shoulder block (land portion) 90 Pneumatic tire 92 Lateral groove (lateral groove) ) 94 Shoulder Block (Land)

Claims (7)

[Claims] 1. A plurality of tires that actually extend along the circumferential direction of the tire
The circumferential groove of the book and extends substantially along the tire axial direction
Multiple land sections separated by multiple lateral grooves
Empty space that is specified for
When it is attached to a vehicle that is a favorite tire and is set to negative camber
In addition, the tires on the land part of the shoulder,
G for circumferential rigidity_os, The shoulder part on the inside in the vehicle width direction
The tire circumferential rigidity of the land part of G_isAnd when G_os<
G_isA pneumatic tire, characterized in that: 2. The tire circumferential length of the land portion of the shoulder portion on the outer side in the vehicle width direction is L _os , and the tire circumferential length of the land portion of the shoulder portion on the vehicle width direction inner side _is L _is . 2. The pneumatic tire according to claim 1, wherein sometimes, L _os <L _is . 3. A pneumatic pneumatic tire according to claim 1, wherein a land portion circumferential reinforcing portion is provided on a tire circumferential side surface of a land portion of the shoulder portion which is located outside the vehicle width direction. tire. 4. When the rigidity in the tire width direction of the land portion of the shoulder portion on the outer side in the vehicle width direction is G _oh , and the rigidity in the tire width direction of the land portion of the shoulder portion on the inner side in the vehicle width direction is G _ih. the pneumatic tire according to any one of claims 1 to 3 characterized in that it is a G _oh> G _ih. 5. A shoulder portion on the outside in the vehicle width direction.
L of the land part in the tire width direction_oh, Inside the vehicle width direction
The length in the tire width direction of the land part of the shoulder part becomes L_ihWhen
When you do L_oh> L_ihClaims characterized in that
5. The pneumatic tire according to 4. 6. The pneumatic pneumatic pump according to claim 4, wherein a land portion width direction reinforcing portion is provided on a side surface in a tire width direction of a land portion of the shoulder portion on the vehicle width direction outside. tire. 7. A plurality of members extending substantially along the tire circumferential direction.
The circumferential groove of the book and extends substantially along the tire axial direction
Multiple land sections separated by multiple lateral grooves
Empty space that is specified for
When mounted on a vehicle with a positive camber
In addition, the tires on the land part of the shoulder,
G for circumferential rigidity_os, The shoulder part on the inside in the vehicle width direction
The tire circumferential rigidity of the land part of G_isAnd when G_os>
G_isA pneumatic tire, characterized in that: