JP6911701B2 - Tire durability test method - Google Patents

Description

The present invention relates to a tire durability test method.

The tires have a belt inside the tread. Running tires are repeatedly deformed. With this tire 2, distortion tends to concentrate on the end of the belt. Peeling may occur at the ends of this belt. Damage to the belt that accompanies this peeling is referred to as breaker edge loose (hereinafter, also referred to as BEL). This BEL resistance is one evaluation item of tire durability.

Various test methods for this BEL have been studied. For example, Japanese Patent Application Laid-Open No. 2015-55581 discloses a test method for reproducing BEL generated in an actual vehicle. Japanese Unexamined Patent Publication No. 2015-141017 discloses a test method for generating BEL in a short time.

JP 2015-55581 JP 2015-141017

In the BEL test method, tire wear and heat generation may cause other problems, and BEL may not be generated. For example, depending on the test method, the shoulders of the tread may wear completely before BEL occurs. Also, due to the temperature rise of the shoulder of the tread, blow (foaming due to heat) may occur before BEL occurs.

An object of the present invention is to provide a test method capable of efficiently evaluating a tire breaker edge looseness.

The tire test method according to the present invention is a breaker edge loose test method. This test method includes a slip running step of imparting a slip angle to the test tire and running the test tire, and a straight running step of running the test tire straight. The traveling time of the slip traveling process is Ts, the traveling time of the straight traveling process is Tn, and the traveling time obtained by combining the traveling time Ts and the traveling time Tn is Tt. At this time, the ratio of the traveling time Ts to the traveling time Tt is 0.2 or more and 0.6 or less.

Preferably, the test method comprises a plurality of slip running steps. In this test method, the straight running step is executed during the slip running step.

Each slip running process includes an angle gradual running step in which the slip angle changes from 0 (°) to an absolute value | θs |, a constant angle running step in which the slip angle is set to a constant absolute value | θs |, and a slip angle. The angle gradually decreases from the absolute value | θs | to 0 (°).

In the slip traveling process, the maximum value of the slip angle is set to the absolute value | θs |. Preferably, the absolute value | θs | is 0.5 (°) or more and 5 (°) or less.

Preferably, the traveling time ts of each slip traveling process is 5 (sec) or more and 30 (sec) or less.

Preferably, the product | θs | · ts of the running time ts of each slip running step and the absolute value | θs | is 10 (° · sec) or more and 50 (° · sec) or less.

Preferably, in each slip traveling process, the traveling time of the constant angle traveling process is longer than the traveling time of the gradually increasing angle traveling process.

Preferably, in each slip traveling process, the traveling time of the constant angle traveling process is longer than the traveling time of the gradually decreasing angle traveling process.

Preferably, the internal pressure of the test tire is 40% or more and 100% or less of the normal internal pressure.

Preferably, in the slip running and the straight running, a load F in the vertical direction is applied to the test tire. The load F is 80% or more and 150% or less of the normal load.

Preferably, the test tire is provided with a camber angle in the slip running and the straight running.

In the test method according to the present invention, the slip traveling process and the straight traveling process are executed. The traveling time Ts of the slip traveling process and the traveling time Tn of the straight traveling process are set to a predetermined ratio. As a result, BEL can be generated while suppressing the temperature rise of the shoulder of the tread of the tire. In this test method, the BEL of the tire can be evaluated efficiently.

FIG. 1 is a partial cross-sectional view of a tire tested by the tire test method according to the embodiment of the present invention. FIG. 2 is a conceptual diagram showing a testing machine for testing the tire of FIG. FIG. 3 is an explanatory view of the testing machine viewed in the direction of arrow III in FIG. FIG. 4 is another explanatory view of the test method using the testing machine of FIG. FIG. 5 is a graph showing the relationship between the slip angle and the time in the test method using the testing machine of FIG.

Hereinafter, the present invention will be described in detail based on preferred embodiments with reference to the drawings as appropriate.

FIG. 1 illustrates the pneumatic tire 2. Here, the test method according to the present invention will be described by taking the tire 2 as an example. In FIG. 1, the vertical direction is the radial direction of the tire 2, the left-right direction is the axial direction of the tire 2, and the direction perpendicular to the paper surface is the circumferential direction of the tire 2. The alternate long and short dash line CL in FIG. 1 represents the equatorial plane. The shape of the tire 2 is symmetrical with respect to the equatorial plane except for the tread pattern.

The tire 2 includes a tread 4, a pair of sidewalls 6, a pair of beads 8, a carcass 10, a belt 12 and a band 14. The tread 6 forms a tread surface 16 that touches the road surface. Each sidewall 6 extends radially inward from the edge of the tread 4. Each bead 8 is located radially inside the sidewall 6. The carcass 10 extends along the tread 4 and the pair of sidewalls 6 and spans one axial bead 8 and the other bead 8. The belt 12 is located inside the tread 4 in the radial direction. The belt 12 is laminated on the carcass 10. The band 14 is located inside the tread 4 in the radial direction. The band 14 is laminated on the outer side in the radial direction of the belt 12.

The belt 12 includes an inner layer 18 and an outer layer 20 laminated on the outer side of the inner layer 18. Each of the inner layer 18 and the outer layer 20 is composed of a large number of parallel cords and topping rubbers. Each cord is inclined with respect to the equatorial plane. The absolute value of this inclination angle is usually 10 ° or more and 35 ° or less. The inclination direction of the cord of the inner layer 18 and the inclination direction of the cord 20 of the outer layer 20 are opposite to the equatorial plane. The preferred material for the cord is steel. This cord may consist of organic fibers.

The axial end 12a of the belt 12 is located inside the axial end of the tread 4. Although not shown, the axial other end of the belt 12 is located inside the axial other end of the tread 4. The belt 12 extends from the vicinity of one end in the axial direction of the tread 4 to the vicinity of the other end. The belt 12 reinforces the carcass 10. The belt 12 includes two layers, an inner layer 18 and an outer layer 20, but the belt 12 may have one layer or three or more layers.

FIG. 2 shows a drum type testing machine 22 as an example of the testing machine used in the test method of the present invention. FIG. 2 shows the tire 2 together with the testing machine 22. The testing machine 22 includes a tire support portion 24 and a drum support portion 26. Although not shown, the testing machine 22 includes a control device. In this testing machine 22, the arrow X in FIG. 1 is directed forward in the front-rear direction, the arrow Y is directed left in the left-right direction, and the arrow Z is directed upward in the vertical direction.

The tire support portion 24 includes a spindle 28 and a rim 30. Although not shown, the tire support portion 24 includes a drive motor, a load device, a slip angle imparting mechanism, and a camber angle imparting mechanism. A rim 30 is detachably attached to the tip of the spindle 28. The tire 2 is incorporated in the rim 30.

The drive motor has a function of rotating the tire 2 attached to the spindle 28. The load device has a function of moving the tire 2 in the vertical direction. The load device has a function of applying a downward load to the tire 2. The slip angle imparting mechanism has a function of imparting a slip angle to the tire 2. The camber angle imparting mechanism has a function of imparting a camber angle to the tire 2.

The drum support portion 26 includes a drum 32. Although not shown, the drum support 26 includes a drum drive motor. The drum 32 has a cylindrical shape. The axis of the drum 32 is in the left-right direction. The outer peripheral surface of the drum 32 forms a road surface 34. The tire 2 runs on the road surface 34. The drum drive motor has a function of rotating the drum 32. The drum 32 is rotatable about its axis as a rotation axis.

The control device controls the tire support portion 24 and the drum support portion 26. The control device adjusts the rotation speed, slip angle, camber angle, and load in the vertical direction of the tire 2 to the set values. Further, the control device adjusts the rotation speed of the drum of the drum support portion 26 to a set value. The control device has a function of controlling the tire support portion 24 and the drum support portion 26 to execute the test according to a procedure preset by a program or the like.

FIG. 3 shows a plan view in the direction of arrow III in FIG. The alternate long and short dash line Lx in FIG. 3 represents a straight line extending in the front-rear direction. The alternate long and short dash line Ly is a straight line extending in the left-right direction. This straight line Ly extends parallel to the axis of the drum 32. The alternate long and short dash line La represents the rotation axis of the tire 2. The alternate long and short dash line Lm represents the center line in the width direction of the tire 2 orthogonal to the rotation axis La.

The double-headed arrow SA represents the slip angle of the tire 2. This slip angle SA is obtained as an angle formed by the straight line Lx and the center line Lm. The slip angle SA of the tire 2 shown in FIG. 3 is defined as a positive slip angle, and the slip angle SA that is inclined in the opposite direction to the straight line Lx is defined as a negative slip angle.

FIG. 4 shows a cross section perpendicular to the circumferential direction of the tire 2. The arrow Lz in FIG. 4 represents a straight line orthogonal to the road surface 34 of the drum 32. The double-headed arrow CA represents the camber angle of the tire 2. This camber angle CA is obtained as the angle formed by the straight line Lz and the equatorial plane CL.

The test method according to the present invention will be described using the tire 2 and the testing machine 22. This test method includes a preparatory step and a running step.

In the preparatory step, the tire 2 is incorporated into the rim 30. The tire 2 is filled with air. The internal pressure of the tire 2 is set to a predetermined test internal pressure P. The rim 30 is attached to the spindle 28. In this way, the tire 2 is mounted on the testing machine 22. The tire 2 is provided with a preset camber angle θc. This camber angle θc may be 0 (°). In the traveling process, the tire 2 is pressed against the road surface 34 with a preset load F.

This traveling process will be described with reference to FIG. The traveling process includes a plurality of straight traveling processes, a plurality of first slip traveling processes, and a plurality of second slip processes. In each straight-ahead traveling step, the tire 2 is traveled in a state where the slip angle SA is set to 0 (°), in other words, in a state where the slip angle SA is not applied. In each first slip traveling step, the tire 2 is traveled in a state where the tire 2 is provided with a positive slip angle SA. In each second slip traveling step, the tire 2 is traveled in a state where the tire 2 is provided with a negative slip angle SA.

The traveling time (t1-t0) from the start time t0 to the time t1 and the straight traveling process are executed. The tire 2 is run with the slip angle SA set to 0 (°). In this traveling time (t1-t0), the tire 2 is allowed to travel straight.

The first slip traveling step is executed during the traveling time (t4-t1) from the time t1 to the time t4. The slip angle SA changes from 0 (°) to θs during the time from time t1 to time t2 (t2-t1). The tire 2 is run in a state where a constant slip angle θs is given for a time from time t2 to time t3 (t3-t2). During the time from time t3 to time t4 (t4-t3), the slip angle SA changes from θs to 0 (°).

Following the first slip traveling process, a straight traveling process is executed. As described above, in this straight running process, the slip angle SA is 0 (°) and the tire 2 is run. The tire 2 is allowed to travel straight during the traveling time (t5-t4) from the time t4 to the time t5.

The running time (t8-t5) from the time t5 to the time t8, the second slip running step is executed. In the second slip traveling step, the slip angle SA changes from 0 (°) to −θs during the time (t6-t5) from the time t5 to the time t6. After that, the tire 2 is run in a state where a constant slip angle −θs is given for a time from time t6 to time t7 (t7-t6). Subsequently, the slip angle SA changes from −θs to 0 (°) during the time from time t7 to time t8 (t8-t7).

This traveling process includes a straight-ahead process, a first slip-traveling process, a straight-ahead process, and a second slip-traveling process as one cycle. In this traveling process, this cycle is repeatedly executed. This cycle is repeated until BEL occurs on the tire 2. If BEL does not occur, the traveling process is completed within a preset test time.

In this test method, the slip angle SA is changed from 0 (°) to θs in the first slip traveling step. In the second slip traveling step, the slip angle SA is changed from 0 (°) to −θs. In the present invention, the change of the slip angle SA from 0 (°) to the absolute value | θs | is called the gradual increase of the slip angle SA, and the change of the slip angle SA from the absolute value | θs | to 0 (°). Is referred to as a gradual decrease in slip angle SA.

In this test method, the slip angle SA gradually increases from 0 (°) to an absolute value | θs | at time (t2-t1) and time (t6-t5). This time (t2-t1) and time (t6-t5) are referred to as gradual increase times. On the other hand, at time (t4-t3) and time (t8-t7), the slip angle SA gradually decreases from the absolute value | θs | to 0 (°). This time (t4-t3) and time (t8-t7) are referred to as tapering time.

In the traveling process of this test method, an absolute value | θs | is given to the tire 2 as a slip angle SA. By giving this absolute value | θs |, a lateral force is generated in the tire 2. This lateral force causes mechanical fatigue on the shoulder of the tread 4. By giving this absolute value | θs |, the generation of BEL is promoted. In this test method, BEL is likely to occur.

In this traveling process, a slip traveling process and a straight traveling process are executed. The presence of this straight-ahead traveling process prevents the load from being excessively concentrated on the shoulder of the tread 4. By executing the straight-ahead traveling process after the slip traveling process, heat generation of the shoulder of the tread 4 is suppressed. As a result, it is suppressed that the shoulder of the tread 4 is completely worn before BEL occurs, and that problems such as blow due to the temperature rise of the shoulder occur. This test method can properly evaluate the BEL resistance while suppressing the occurrence of other defects.

By setting the traveling time Tn of the straight traveling process to be long, the occurrence of BEL is promoted while suppressing the occurrence of other defects. In other words, by setting the traveling time Ts of the slip traveling process to be short, the occurrence of BEL is promoted while suppressing the occurrence of other defects. From this viewpoint, the ratio of the traveling time Ts (Ts / Tt) to the traveling time Tt, which is the sum of the traveling time Ts and the traveling time Tn, is preferably 0.6 or less. On the other hand, by lengthening the running time Ts of the slip running process, the time until BEL occurs can be shortened. By lengthening the traveling time Ts, the test time can be shortened. From this point of view, the ratio (Ts / Tt) is preferably 0.2 or more.

The test method of the present invention is not limited to the one in which a certain cycle is repeatedly executed as shown in FIG. In this test method, a straight running step and a slip running step may be executed. In the present invention, the running time Tn is calculated as the total running time of the straight running process from the start of the test to the end of the test. The running time Ts is calculated as the total running time of the slip running process from the start of the test to the end of the test.

In this test method, a plurality of straight running steps, a plurality of first slip running steps, and a plurality of second slip running steps are executed, but the present invention is not limited thereto. In this test method, the generation of BEL is generated while suppressing the occurrence of other defects by setting the ratio of the traveling time Ts (Ts / Tt) to the traveling time Tt to a predetermined ratio, including the straight running process. Prompted.

In this test method, the first slip running step and the second slip running step are executed, but the test method is not limited to this. In the test method according to the present invention, the first slip traveling step and the straight traveling step for imparting the slip angle θs may be executed. Further, in this test method, a second slip traveling step and a straight traveling step for imparting a slip angle −θs may be executed.

This slip traveling step includes an angle gradually increasing traveling step in which the slip angle SA gradually increases from 0 (°) to an absolute value | θs |, a constant angle traveling step in which the slip angle is set to a constant absolute value | θs |, and a slip angle. It includes an angle gradual running step in which SA gradually decreases from the absolute value | θs | to 0 (°). In this constant angle traveling process, a predetermined amount of lateral force is continuously applied to the tire 2 during this traveling. This constant angle traveling process imparts mechanical fatigue to the shoulders of the tread 4. BEL is likely to occur on the tire 2.

In this test method in which the absolute value | θs | is large, a large lateral force is generated in the tire 2. This lateral force contributes to the generation of BEL. From this point of view, the absolute value | θs | is preferably 0.5 (°) or more, and more preferably 1.5 (°) or more. On the other hand, in the test method in which the absolute value | θs | is small, the heat generation of the tread 4 is suppressed. As a result, it is possible to prevent the tire 2 from having a problem other than BEL. From this point of view, the absolute value | θs | is preferably 5 (°) or less, and more preferably 4 (°) or less.

Here, the running time of one slip running process is defined as ts. For example, each of the traveling time (t4-t1) of the first slip traveling process and the traveling time (t8-t5) of the second slip traveling process is the traveling time ts. In this test method, the straight running process and the slip running process are alternately repeated. As a result, the traveling time ts of one slip traveling process is shortened. Thereby, the heat generation of the tread 4 can be further suppressed. In this test method, the occurrence of BEL is further promoted while suppressing the occurrence of other defects.

In the test method in which the running time ts of one slip running step is long, the lateral force is continuously generated on the tire 2 for a long time. The continuous generation of lateral force for a long time contributes to the generation of BEL. From this viewpoint, the traveling time ts is preferably 5 (sec) or more, and more preferably 10 (sec) or more. On the other hand, in this test method in which the traveling time ts is short, the heat generation of the tread 4 is suppressed. As a result, it is possible to prevent the tire 2 from having a problem other than BEL. From this viewpoint, the traveling time ts is preferably 30 (sec) or less, and more preferably 20 (sec) or less.

In the test method in which the product | θs | · ts of the absolute value | θs | and the traveling time ts is large, the generation of BEL is promoted. From this point of view, the product | θs | · ts is preferably 10 (° · sec) or more, and more preferably 20 (° · sec) or more. On the other hand, in the test method in which the product | θs | · ts is small, it is possible to suppress the occurrence of defects other than BEL. From this point of view, the product | θs | · ts is preferably 50 (° · sec) or less, and more preferably 40 (° · sec) or less.

In this traveling process, the generation of BEL is promoted by lengthening the traveling time of the traveling process having a constant angle. The time until the occurrence of BEL is shortened. This test is efficiently carried out by lengthening the running time of the constant angle running process. From this point of view, in each slip traveling process, it is preferable that the traveling time of the constant angle traveling process is longer than the traveling time of the gradually increasing angle traveling process. In each slip traveling process, the traveling time of the constant angle traveling process is preferably longer than the traveling time of the gradually decreasing angle traveling process. Further, in each slip traveling process, it is preferable that the traveling time of the constant angle traveling process is longer than the traveling time of the traveling time of the angle gradual increasing traveling process and the traveling time of the angle gradual decreasing traveling process.

By running the tire 2 having a low test internal pressure P, the deterioration of the tire 2 is promoted. This promotes the generation of BEL. From this viewpoint, the test internal pressure P is preferably 100% or less of the normal internal pressure, more preferably 90% or less, and particularly preferably 80% or less. On the other hand, the tire 2 having a high test internal pressure P generates an appropriate tension in each part. Running the tire 2 may cause the same problems as running the actual vehicle. From this viewpoint, the test internal pressure P is preferably 40% or more, more preferably 50% or more, and particularly preferably 60% or more of the normal internal pressure.

In the test method in which the load F in the vertical direction is large, the deterioration of the tire 2 is promoted. This promotes the generation of BEL. From this viewpoint, the load F is preferably 80% or more of the normal load, more preferably 90% or more, and particularly preferably 100% or more. On the other hand, in this test method in which the load F is small, heat generation of the tire 2 is suppressed. This suppression of heat generation can suppress the occurrence of defects other than BEL. From this viewpoint, the load F is preferably 150% or less of the normal load, more preferably 140% or less, and particularly preferably 130% or less.

Further, in this test method, it is preferable that the tire 2 is provided with a camber angle. By imparting a camber angle CA, the generation of BEL is promoted. Increasing the camber angle CA promotes the generation of BEL. From this point of view, the absolute value of this camber angle CA is preferably 2 ° or more. On the other hand, by reducing the camber angle CA, it is possible to suppress the occurrence of problems other than BEL. From this point of view, the absolute value of this camber angle CA is preferably 4 ° or less.

In the present invention, BEL means damage caused by peeling at the end of the belt 12, but this BEL is not limited to damage caused at the end of the inner layer 18 of the tire 2. This BEL also includes damage that occurs at the edges of the outer layer 20. Further, when the belt 12 is composed of three or more layers, the damage caused at the end of each layer is also included.

As used herein, the term "regular rim" means a rim defined in the standard on which Tire 2 relies. The "standard rim" in the JATTA standard, the "Design Rim" in the TRA standard, and the "Measuring Rim" in the ETRTO standard are regular rims. In the present specification, the normal internal pressure means the internal pressure defined in the standard on which the tire 2 relies. The "maximum air pressure" in the JATMA standard, the "maximum value" in the "TIRE LOAD LIMITS AT VARIOUS COLD INFLATION PRESSURES" in the TRA standard, and the "INFLATION PRESSURE" in the ETRTO standard are regular internal pressures. In the present specification, the normal load means the load defined in the standard on which the tire 2 relies. The "maximum load capacity" in the JATTA standard, the "maximum value" in the "TIRE LOAD LIMITS AT VARIOUS COLD INFLATION PRESSURES" in the TRA standard, and the "LOAD CAPACITY" in the ETRTO standard are normal loads.

Hereinafter, the effects of the present invention will be clarified by Examples, but the present invention should not be construed in a limited manner based on the description of these Examples.

[Example 1]
Test tires were prepared. This tire size was "330 / 710R18". This tire was mounted on the drum type testing machine shown in FIG. For this tire, the internal pressure, load and running speed were as follows. Other test conditions were as shown in Table 1 and the BEL resistance test was performed. In Table 1, "A" in the column of the traveling process represents a traveling process in which the straight traveling process and the slip traveling process are repeatedly executed as shown in FIG. "B" in this column represents a traveling process of straight traveling only. The ts (sec) in Table 1 represents the traveling time (t4-t1). In this test method, the running time (t8-t5) was set to the same length as the running time (t4-t1).
Internal pressure 130 (kPa)
Load 6.5 (kN)
Speed 220 (km / h)

[Comparative Example 1]
The BEL resistance test was carried out in the same manner as in Example 1 except that the vehicle was run without giving a slip angle.

[Comparative Example 2, Comparative Example 3 and Example 2-3]
The BEL resistance test was carried out in the same manner as in Example 1 except that the ratio (Ts / Tt) was as shown in Table 1.

[Example 4-10]
The BEL resistance test was carried out in the same manner as in Example 1 except that the absolute value | θs | and the running time ts of the slip running step were as shown in Table 2.

[BEL evaluation]
In these tests, the time until BEL occurred and the state of BEL occurrence were evaluated. “BEL generation time” in Table 1 represents the time until BEL occurs. This time is represented by an index with Example 1 as 100. The smaller this index is, the shorter the time until BEL occurs. The smaller this index is, the more preferable it is. The “BEL generation scale” in Table 1 represents the BEL generation status. The evaluation was made on a 5-point scale, with 1 being the one in which BEL was not generated and 5 being the one in which BEL was generated over the entire circumference.

As shown in Tables 1 and 2, the test methods of Examples are more suitable for evaluating BEL than the test methods of Comparative Examples. From this evaluation result, the superiority of the present invention is clear.

The test method described above can be widely applied to the evaluation of BEL of various tires.

2 ... Tire 4 ... Tread 12 ... Belt 16 ... Tread surface 22 ... Testing machine 24 ... Tire support 26 ... Drum support 28 ... Spindle 30 ... Rim 32 ... Drum 34 ... Road surface

Claims (11)

This is a test method for breaker edge looseness.
A slip running process that gives a slip angle to the test tire and runs it,
It is equipped with a straight-ahead running process that allows the above test tires to run straight-ahead.
When the traveling time of the slip traveling process is Ts, the traveling time of the straight traveling process is Tn, and the traveling time obtained by combining the traveling time Ts and the traveling time Tn is Tt, the above traveling time Tt with respect to the traveling time Tt. A tire test method in which the ratio of running time Ts is 0.2 or more and 0.6 or less. It has multiple slip running processes as described above.
The test method according to claim 1, wherein the straight running step is executed during the slip running step. Each slip running process has an angle gradual running process in which the slip angle changes from 0 (°) to an absolute value | θs |.
A constant angle running process in which the slip angle is set to a constant absolute value | θs |
The angle gradual reduction running process in which the slip angle gradually decreases from the absolute value | θs | to 0 (°),
The test method according to claim 2. In the slip running process, the maximum value of the slip angle is set to the absolute value | θs |.
The test method according to claim 2 or 3, wherein the absolute value | θs | is 0.5 (°) or more and 5 (°) or less. The test method according to any one of claims 2 to 4, wherein the traveling time ts of each slip traveling process is 5 (sec) or more and 30 (sec) or less. The fourth or fifth claim, wherein the product | θs | · ts of the running time ts of each slip running step and the absolute value | θs | is 10 (° · sec) or more and 50 (° · sec) or less. Test method. The test method according to any one of claims 2 to 6, wherein in each slip traveling process, the traveling time of the constant angle traveling process is longer than the traveling time of the gradually increasing angle traveling process. The test method according to any one of claims 2 to 7, wherein in each slip traveling process, the traveling time of the constant angle traveling process is longer than the traveling time of the gradually decreasing angle traveling process. The test method according to any one of claims 1 to 8, wherein the internal pressure of the test tire is 40% or more and 100% or less of the normal internal pressure. The test according to any one of claims 1 to 9, wherein a load F in the vertical direction is applied to the test tire in the slip running and the straight running, and the load F is 80% or more and 150% or less of the normal load. Method. The test method according to any one of claims 1 to 10, wherein a camber angle is given to the test tire in the slip running and the straight running.

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