JP2010163081A - Tire and mounting method for tire - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a tire improving initial performance of cornering of the tire as a whole by setting rigidity of a vehicular outside to be smaller than rigidity of a vehicular inside in the tire mounted to a rear wheel, and also to provide a mounting method for the tire. <P>SOLUTION: In the mounting method for a tire, pneumatic tires 1 are mounted to both of right and left front wheels and both of right and left rear wheels of a vehicle. In the pneumatic tire 1, negative ratios of a right side and a left side in a tire width direction on a tread surface divided by a tire equator line as a boundary, are different from each other. The pneumatic tires 1 are mounted to the front wheels of the vehicle in a direction where the side having the smaller negative ratio is set to be the vehicular outside, and the pneumatic tires 1 are mounted to the rear wheels of the vehicle in a direction where the side having the smaller negative ratio is set to be the vehicular inside. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a tire and a tire mounting method, and more particularly to a tire and a tire mounting method that place importance on the maneuverability during cornering.

  For example, a tire with a left-right asymmetric pattern used for circuit driving or the like has a structure in which the rigidity on the outer side of the mounting is increased in order to improve the maneuverability during cornering.

  Normally, tires that are cornering are deformed so as to be dragged toward the inside in the mounting direction by input from the road surface, and at the same time, the tread surface that is in contact with the road surface is grounded on a wider area than the inner side of the mounting . For this reason, in order to make the ground contact area on the outer side of the tread surface larger than the ground surface on the inner side of the mounting, the area of the groove on the outer side of the tire equator line is set smaller than that on the inner side of the tire. In addition, the ratio of the groove | channel with respect to the whole contact area is called a negative ratio, and adjusting this negative ratio suitably is performed (for example, refer patent document 1).

  With such a tire, the speed during cornering can be kept high, while when changing the direction of the vehicle in the early stage of cornering, the front wheels try to generate a force inward of the cornering, whereas the rear wheels Excessive force for moving the vehicle straight remains, and as a result, even if the driver turns off the steering, the vehicle is unlikely to change its direction, so-called understeer is likely to occur. This understeer phenomenon is not only difficult for cornering, but also for emergency avoidance when avoiding obstacles and when you want to increase the slip angle of the rear wheel (drift angle of the rear wheel relative to the direction of travel) when drifting. It becomes. In order to avoid this phenomenon, conventionally, the grip force of the tire attached to the rear wheel is made smaller than the tire attached to the front wheel.

JP 9-1332011 A

  However, as described above, when the front wheel side tire and the rear wheel side tire are set to different gripping forces, there is a problem that the number of man-hours for managing the tire increases. In addition, there is a problem that the wear of the same part of the tire easily progresses for each of the front wheel and the rear wheel, and the life is shortened.

  An object of the present invention is to provide a tire having a small tire management man-hour and a long life, and a tire mounting method.

  The first feature of the present invention is a tire (pneumatic tire 1) in which the negative ratio is different between the left side and the right side in the tire width direction on the tread surface (tread surface 10) with respect to the tire equator line (tire equator line CL). Is mounted on the left and right sides of the front and rear wheels of the vehicle, and the front wheels of the vehicle are fitted with tires so that the side with the smaller negative ratio faces the outside of the vehicle. The gist is to attach the tire to the rear wheel in such a direction that the side with the smaller negative ratio becomes the inside of the vehicle.

  Thus, by setting the rigidity on the vehicle outer side smaller than the rigidity on the vehicle inner side in the tire mounted on the rear wheel, the initial performance of cornering can be improved as a whole tire. That is, in the initial stage of cornering, a phenomenon in which the rear wheels try to keep the straight traveling state excessively is suppressed, and as a result, the turning ability during cornering is improved.

  Another feature is that the tires (pneumatic tires 1) mounted on the left and right sides of the front and rear wheels of the vehicle each have a tread pattern of the same shape.

  In other features, a tire (pneumatic tire 1) having a negative ratio that is different between the left side and the right side in the tire width direction on the tread surface (tread surface 10) with respect to the tire equator line (tire equator line CL), When attaching a tire to the front wheel of the vehicle, at least one of the shoulder portion (shoulder portion 6) and the sidewall portion (sidewall portion 7), attach the tire in such a direction that the side with the smaller negative ratio becomes the outside of the vehicle, When the tire is mounted on the rear wheel of the vehicle, the gist is that an instruction to mount the tire in a direction in which the side with the smaller negative ratio is the inside of the vehicle is displayed.

  In other features, a block row (block row 14) is formed on the tread surface (tread surface 10) on the side having a smaller negative ratio, and a rib row (rib row) on the tread surface on the side having the larger negative ratio. 25) is formed.

  Another feature is that the radius of curvature of the carcass (carcass 3) on the side where the negative ratio is small is set larger than the radius of curvature of the carcass on the side where the negative ratio is large.

  In another feature, the height (height H1) of the maximum width position of the carcass (carcass 3) on the side where the negative ratio is small is the height (height H2) of the maximum width position of the carcass on the side where the negative ratio is large. ) Is set lower.

  According to the tire and the tire mounting method according to the present invention, the initial performance of cornering can be improved as a whole tire by setting the rigidity on the outer side of the vehicle smaller than the rigidity on the inner side of the vehicle in the tire mounted on the rear wheel. it can.

1 is a cross-sectional view in the width direction of a pneumatic tire according to a first embodiment of the present invention. It is the figure which looked at the pneumatic tire by a 1st embodiment of the present invention from the front. 1 is a layout diagram of pneumatic tires in an entire vehicle mounted using a method according to a first embodiment of the present invention.

  Hereinafter, details of a tire according to an embodiment of the present invention will be described with reference to the drawings. However, it should be noted that the drawings are schematic, and the thicknesses and ratios of the material layers are different from actual ones. Therefore, specific thicknesses and dimensions should be determined in consideration of the following description. Moreover, the part from which the relationship and ratio of a mutual dimension differ also in between drawings is contained.

[First embodiment]
First, a pneumatic tire according to a first embodiment of the present invention will be described.

<Schematic configuration of pneumatic tire>
FIG. 1 is a cross-sectional view in the width direction of a pneumatic tire according to a first embodiment of the present invention.

  As shown in FIG. 1, a pneumatic tire 1 includes a pair of annular bead cores 2 and 2 that are spaced apart in the tire width direction, and the bead cores 2 and 2 are connected in a toroidal shape to form a tire skeleton. A carcass 3, a belt layer 4 disposed on the top 3 a of the carcass 3, a tread portion 5 provided on the top 3 a of the carcass 3, and both sides of the tread portion 5 in the tire width direction. The shoulder part 6, the side wall part 7 which comprises a tire side surface, and the bead part 9 which has the bead core 2 and the stiffener 8 are provided. The bead core 2 is configured using, for example, a steel cord.

<Tread pattern shape>
FIG. 2 is a front view of the pneumatic tire according to the first embodiment of the present invention.

The tread pattern according to the present embodiment is asymmetrical with the left and right tread pattern shapes being asymmetrical with the tire equator line CL at the center in the tire width direction as a boundary. The negative ratio is low on the right side of FIG. It is formed in a high shape. Here, the “negative ratio” refers to the ratio of the area of the groove portion to the area of a predetermined range on the tread surface 10. For example, a groove portion in an area 100 cm ² of the predetermined range 30 cm ² occupies, when the contact area is 70cm ² occupied, negative ratio is 0.3. Therefore, the smaller the negative ratio, the smaller the proportion of the groove area, and the greater the contact area with the road surface, thereby improving the rigidity of the tire.

  A central side circumferential groove 11 extending along the circumferential direction is formed in the tire width direction central portion of the tread surface 10, and the right end of the central side circumferential groove 11 has a substantially triangular shape on the right side in the tire width direction. A wave land 12 that continuously protrudes is formed along the circumferential direction. On the right side of the wavy land portion 12, a block row 14 composed of a plurality of blocks 13 arranged intermittently along the circumferential direction is formed. The respective blocks 13 are separated from each other by a width direction groove 15 extending along the tire width direction, and a narrow groove 16 extending in the width direction is formed at the circumferential center of each block 13. Therefore, the substantially triangular triangular grooves 17 are arranged between the waved land portion 12 and the block 13 along the circumferential direction.

  On the other hand, a circumferential land portion 21 extending continuously along the circumferential direction is formed on the left side of the tire equator line CL, and continuously on the left side of the circumferential land portion 21 along the circumferential direction. An extending lateral circumferential groove 22 is formed. A rib 23 extending continuously in the circumferential direction is formed on the left side of the lateral circumferential groove 22, and a narrow groove 24 extending in the width direction is formed on the rib 23. A rib row 25 is constituted by the plurality of ribs 23.

  As described above, in the tread pattern of FIG. 2, the negative ratio of the right tread surface 10 across the tire equator line CL (ratio of the area of the groove portion to the total area of the tread surface) sandwiches the tire equator line CL. And set to a value smaller than the negative ratio of the left tread surface 10.

<Tire layout>
FIG. 3 is a layout diagram of pneumatic tires in the entire vehicle mounted using the method according to the first embodiment of the present invention.

  In this embodiment, a total of four pneumatic tires are mounted on the left and right sides of the front and rear wheels of the vehicle, but each tire is formed in the same tread pattern. That is, the pneumatic tire 1 having the arrangement shown in FIG. 2 is arranged on the right side of the front wheel and the left side of the rear wheel, and the pneumatic tire 1 in the state where the left and right sides of FIG. Is arranged. Accordingly, the front wheel is set so that the negative ratio outside the vehicle on the tread surface 10 is smaller than the negative ratio inside the vehicle, and the rear wheel has a negative ratio inside the vehicle on the tread surface 10 higher than the negative ratio outside the vehicle. It is set to be smaller.

  Specifically, the pneumatic tire 1 mounted on the right side of the front wheel is mounted in the same direction as the pneumatic tire described in FIG. 2, and the negative ratio on the right side of the tire equator line is smaller than that on the left side. Is set to Further, the pneumatic tire 1 described in FIG. 2 is mounted on the left side of the front wheel so as to be reversed left and right, and the negative ratio on the left side of the tire equator line CL is set to a value smaller than that on the right side. .

  Similarly, the pneumatic tire 1 mounted on the right side of the rear wheel is the same as the layout mounted on the left side of the front wheel. The pneumatic tire 1 described in FIG. Also, the negative ratio on the left side is set to a value smaller than that on the right side. Also, on the left side of the rear wheel, the same arrangement as that on the right side of the front wheel is installed, and the same arrangement as the pneumatic tire 1 described in FIG. 2 is installed, and the negative ratio on the right side of the tire equator line CL is installed. Is set to a value smaller than the left side.

<Operation effect>
(1) A pneumatic tire in which the pneumatic tires 1 having different negative ratios on the left and right sides in the tire width direction on the tread surface 10 with the tire equator line CL as a boundary are mounted on the left and right sides of the front and rear wheels of the vehicle. In the mounting method, a pneumatic tire 1 is mounted on a front wheel of the vehicle in such a direction that a side having a smaller negative ratio faces the vehicle, and a vehicle having a smaller negative ratio is mounted on the rear wheel of the vehicle. In this method, the pneumatic tire 1 is mounted in the direction toward the inside.

  Thus, by setting the rigidity on the outside of the vehicle smaller than the rigidity on the inside of the vehicle in the pneumatic tire mounted on the rear wheel, the initial performance of cornering can be improved as a whole tire. That is, in the initial stage of cornering, a phenomenon in which the rear wheels try to keep the straight traveling state excessively is suppressed, and as a result, the turning ability during cornering is improved.

  (2) Since the pneumatic tires 1 to be mounted on the left and right sides of the front and rear wheels of the vehicle have tread patterns with the same shape, the front and rear wheels of the pneumatic tire 1 having the same structure are arranged reversely. Can be installed on both the left and right sides of the Therefore, compared with the case where the front wheels and the rear wheels are distinguished as separate pneumatic tires, the number of man-hours for managing the tire is reduced, and the life is also increased due to a decrease in wear.

  (3) As shown in FIG. 2, a block row 14 is formed on the tread surface 10 on the side where the negative ratio is small, and a rib row 25 is formed on the tread surface 10 on the side where the negative ratio is large. Yes. Thus, by forming the block row 14 and the rib row 25, the negative ratio can be easily adjusted.

[Second Embodiment]
Next, a second embodiment of the present invention will be described.

  As shown in FIG. 1 described above, in the present embodiment, the height of the maximum width position of the carcass 3 in the tire width direction is such that the height H1 on the right side of the tire equator line CL is lower than the height H2 on the left side. Is set to a value. Here, the heights H1 and H2 are the lengths along the tire radial direction between the inner end in the tire radial direction of the bead portion 9 and the maximum width position of the cross section in the tire width direction of the carcass 3.

  Although not shown, the radius of curvature of the carcass 3 on the side with the lower negative ratio is set larger than the radius of curvature of the carcass 3 on the side with the higher negative ratio, with the tire equator line CL as a boundary. ing. That is, in the pneumatic tire 1 on the right side of the front wheel and the left side of the rear wheel in FIG. 3, the carcass 3 on the right side of the tire equator line CL is formed in a substantially linear cross-sectional shape, and the cross-sectional shape of the carcass 3 on the left side is a substantially arc shape. Is formed. In the pneumatic tire 1 on the left side of the front wheel and the right side of the rear wheel in FIG. 3, the carcass 3 on the left side of the tire equator line CL is formed in a substantially linear cross-sectional shape, and the cross-sectional shape of the right carcass 3 is substantially arc-shaped. Is formed.

  Furthermore, in this embodiment, a display is provided on the surface of the sidewall portion 7 of the pneumatic tire 1. This display clearly indicates an instruction on which part of the front and rear wheels of the vehicle to which the pneumatic tire 1 is to be attached, out of a total of four places.

  As described with reference to FIG. 3, the side with the smaller negative ratio is arranged outside the front wheel and the inside of the rear wheel, and the side with the larger negative ratio is arranged inside the front wheel and outside the rear wheel. Is done.

  Therefore, for example, in the pneumatic tire 1 mounted on the right side of the front wheel, “OUTSIDE for FRONT” and “INSIDE for REAR” are formed on the surface of the sidewall portion 7 on the right side of the tire equator line CL with a smaller negative ratio. The character of is displayed. On the other hand, “INSIDE for FRONT” and “OUTSIDE for REAR” are provided on the surface of the side wall portion 7 of the pneumatic tire 1 mounted on the right side of the front wheel and mounted on the left side of the tire equator line CL with the larger negative ratio. The character of is displayed.

<Operation effect>
(1) The radius of curvature of the carcass 3 on the side where the negative ratio is small is set larger than the radius of curvature of the carcass 3 on the side where the negative ratio is large. Further, the height H1 of the maximum width position of the carcass 3 on the side where the negative ratio is small is set lower than the height H2 of the maximum width position of the carcass 3 on the side where the negative ratio is large.

  Therefore, the input received by the pneumatic tire from the road surface is borne more by the carcass 3 on the side where the negative ratio is smaller than the carcass 3 on the side where the negative ratio is large. Thereby, the rigidity of the shoulder portion 6 on the vehicle outer side of the front wheel can be secured, and as a result, the cornering performance of the front wheel can be improved. Similarly, at the rear wheels, the input burden received from the road surface on the outside of the vehicle is smaller than that on the inside of the vehicle. This suppresses a phenomenon in which the rear wheels excessively keep going straight at the beginning of cornering, thereby making it easier for the vehicle to change the traveling direction.

  In addition, it becomes easy to change the posture of the vehicle in so-called drift running, in which the rear wheel is largely slid and the vehicle is cornered with a large angle with respect to the traveling direction, which is useful for drift competition.

  (2) A pneumatic tire in which the negative ratio is different between the left side and the right side in the tire width direction on the tread surface 10 with the tire equator line CL as a boundary, and the pneumatic tire 1 is attached to the sidewall 7 of the front wheel of the vehicle. When installing, attach the side with the smaller negative ratio facing the outside of the vehicle, and when installing the pneumatic tire 1 on the rear wheel of the vehicle, install the side with the smaller negative ratio facing the inside of the vehicle The instruction to do is displayed. Therefore, even after a pneumatic tire is sold and put on the market, the pneumatic tire can be arranged and installed in a predetermined direction at a predetermined position without making a mistake.

[Other embodiments]
It should not be understood that the descriptions and drawings which form part of the disclosure of the above-described embodiments limit the present invention. From this disclosure, various alternative embodiments, examples and operational techniques will be apparent to those skilled in the art.

  For example, in each of the above-described embodiments, the instruction is displayed on the sidewall portion 7 of the pneumatic tire 1, but may be displayed on the shoulder portion 6.

  Hereinafter, the present invention will be described in more detail through examples.

  The pneumatic tire according to the conventional example and the example of the present invention was assembled to a rim wheel having a tire size of 235 / 45R17 and a rim size of 8.0 J × 17. The internal pressure of the pneumatic tire was set to 210 kPa, and the height of the maximum width position of the carcass and the curvature radius of the sidewall portion were measured.

  In addition, these pneumatic tires were assembled to the front and rear wheels of the vehicle to drive the vehicle, and the cornering power of the front and rear wheels was measured. In this vehicle running experiment, a pneumatic tire having a tire size of 235 / 45R17 was assembled to a rim wheel having a rim size of 8.0 J × 17, the load was 7.5 kN, and the internal pressure was 230 kPa. These results are shown in Table 1.

表１の結果から、本発明例に係る空気入りタイヤの方が従来例よりもコーナリング性が高いことが判明した。

From the results in Table 1, it was found that the pneumatic tires according to the examples of the present invention had higher cornering properties than the conventional examples.

CL tire equator 1 pneumatic tire 3 carcass 6 shoulder 7 side wall 10 tread surface H1, H2 height of maximum width position

Claims (6)

A tire mounting method in which tires having different negative ratios on the left and right sides in the tire width direction on the tread surface from the tire equator line are mounted on the left and right sides of the front and rear wheels of the vehicle,
A tire is attached to the front wheel of the vehicle in such a direction that the side with the smaller negative ratio becomes the vehicle outer side,
A tire mounting method, characterized in that a tire is mounted on the rear wheel of the vehicle in such a direction that the side with a smaller negative ratio becomes the vehicle inner side.   The tire mounting method according to claim 1, wherein tires mounted on the left and right sides of the front and rear wheels of the vehicle have tread patterns having the same shape. Tires with different negative ratios on the left and right sides in the tire width direction on the tread surface with the tire equator line as the boundary
At least one of the shoulder part or the sidewall part,
When attaching tires to the front wheels of the vehicle, attach the side with the smaller negative ratio facing the outside of the vehicle, and when attaching tires to the rear wheels of the vehicle, the side with the smaller negative ratio becomes the inside of the vehicle A tire characterized by instructions for mounting in the direction. A block row is formed on the tread surface on the side where the negative ratio is small,
The tire according to claim 3, wherein a rib row is formed on a tread surface on a side where the negative ratio is large.   5. The tire according to claim 3, wherein a radius of curvature of the carcass on the side where the negative ratio is small is set larger than a radius of curvature of the carcass on the side where the negative ratio is large.   6. The height of the maximum width position of the carcass on the side where the negative ratio is small is set lower than the height of the maximum width position of the carcass on the side where the negative ratio is large. The tire according to claim 1.

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