JP3511299B2 - Set asymmetric pneumatic tire and method of mounting the same - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a set of asymmetric pneumatic tires having different circumferential rigidity at both ends in the axial direction, and a method of mounting the same .

[0002]

2. Description of the Related Art Generally, pneumatic tires have various performances such as dry performance, wet performance, riding comfort performance,
Although abrasion resistance and the like are required, various pneumatic tires have been proposed to improve a plurality of contradictory performances among these performances. Among them, asymmetric pneumatic tires, that is, tires have been proposed. By making the number of belt layers, the number of belt reinforcing layers, the width, etc. on one side and the other side of the equatorial plane different from each other, a pneumatic tire that is able to exhibit good heterogeneous performance on these one side and the other side, respectively. Are known. As such an asymmetric pneumatic tire, for example, by increasing the circumferential rigidity of one side and reducing the circumferential rigidity of the other side, deformation on one side is suppressed and the cushioning function on the other side is improved. It is known that the one side is the outer side of the vehicle on which the vehicle is mounted, so that deformation due to lateral force is suppressed and cornering performance (steering stability) is improved, while the other side is mounted on the vehicle. By being mounted inside, the vibration from the road surface is absorbed to improve the riding comfort performance.

[0003]

However, in such a conventional asymmetric pneumatic tire, no consideration is given to the fact that it is mounted on the front and rear wheels of the vehicle, so that the performance is not sufficient. There is a problem that it can not be fully exerted.

The present invention relates to a set of asymmetric pneumatic tires and tires which can further improve steering stability.
It is intended to provide a wearing method of the.

[0005]

Means for Solving the Problems] The above object, the first
The toroidal carcass layer, the belt layer radially outside the carcass layer, the tread radially outside the belt layer, and the tire inside the belt layer and the tread. A belt reinforcing layer in which reinforcing cords substantially parallel to the equatorial plane are embedded, and an asymmetric pneumatic tire having different circumferential rigidity at both axial ends of the belt reinforcing layer, the vehicle comprising: The asymmetric pneumatic tie of the set is installed so that the front wheel has the side with high circumferential rigidity on the outer side of the mounting and the rear wheel has the side with high rigidity on the inner side of the mounting.
Ki De be accomplished by Ya, the second, the toroidal
The carcass layer is placed on the outside of the carcass layer in the radial direction.
The belt layer, and is arranged on the outer side of the belt layer in the radial direction.
Inside the tread, located between the belt layer and the tread
Embedded with a reinforcing cord that is substantially parallel to the equatorial plane of the tire
A belt reinforcing layer, and both of the belt reinforcing layer in the axial direction.
The circumferential rigidity at the ends is made different from each other.
When installing an asymmetric pneumatic tire in a vehicle, the front wheels of the vehicle
, So that the side with high circumferential rigidity is placed on the outside of the mounting,
On the other hand, the rear wheel has the side with high circumferential rigidity on the inner side of the mounting.
A set of asymmetric pneumatic tires
Ru can be achieved by a method.

[0006]

[Function] Asymmetric pneumatic tires are mounted on the front and rear wheels of the vehicle. At this time, both pneumatic tires mounted on the front wheels are arranged so that the side with high circumferential rigidity comes to the outer side of the mounting. Both the pneumatic tires to be mounted on the rear wheels are arranged opposite to the front wheels, that is, so that the side having high circumferential rigidity is located inside the mounting wheels. At this time, the steering stability is further improved due to the following reasons. That is, when the rear wheel is the drive wheel, a camber angle is given to the rear wheel, so that a high ground pressure is generated inside the mounting of the pneumatic tire mounted on the rear wheel, and the driving force is exerted. However, at this time, if the tires to be mounted on the rear wheels are arranged so that the side with higher circumferential rigidity comes to the inside as described above, the ground contact pressure inside the pneumatic tires on the rear wheels will be even higher. It is possible to obtain a larger driving force. At this time, the pneumatic tires are mounted on the front wheels in the same manner as in the conventional case, so there is no change.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. In FIGS. 1 and 2, reference numeral 11 denotes an asymmetric pneumatic tire mounted on the left front wheel of a vehicle. The tire 11 has a pair of bead portions 12 and 13 and extends from the bead portions 12 and 13 outward in a substantially radial direction. Side wall
14 and 15, and a substantially cylindrical tread portion 16 that connects the outer ends in the radial direction of both sidewall portions 14 and 15. The tire 11 is reinforced by a substantially toroidal carcass layer 17 extending from the one bead portion 12 to the other bead portion 13.
Both side portions in the width direction are folded back around the beads 18 and 19 embedded in the bead portions 12 and 13, respectively, from the axially inner side toward the axially outer side. This carcass layer 17 comprises at least one carcass ply, here one carcass ply.
This carcass ply 20 extends in the radial direction, that is, approximately 90 with respect to the tire equatorial plane E.
Many steel cords that intersect at a certain degree are buried.
A belt layer 24 is provided on the tread portion 16 on the outer side of the carcass layer 17 in the radial direction, and the belt layer 24 has at least two cords made of steel or the like embedded therein.
The belt plies 25 and 26, in this case, are laminated. And these belt plies 25,
The steel cords embedded in the respective 26 are inclined so as to intersect with the equatorial plane E of the tire at an angle of 15 to 35 degrees, and in the belt plies 25 and 26, they are inclined in opposite directions and intersect each other. A tread 29 having wide grooves 28 such as a main groove and a lateral groove is arranged on the tread portion 16 on the outer side in the radial direction of the belt layer 24. 31 is the belt layer
The first reinforcing layer 31 is disposed between the tread 29 and the tread 29 and covers the belt layer 24 over the entire width thereof. The first reinforcing layer 31 has at least one cord in which a cord made of nylon or the like is embedded, In this embodiment, it is composed of two first reinforcing plies 32 and 33, and the cords inside these first reinforcing plies 32 and 33 are arranged substantially parallel to the equatorial plane E of the tire. In addition, a second reinforcing layer 35 that covers only one axial end of the first reinforcing ply 33 is disposed between the first reinforcing ply 33 and the tread 29 that are located on the outer side in the radial direction. Is composed of at least one, in this embodiment, one second reinforcing ply 36 in which a cord made of nylon or the like is embedded. The cords in the second reinforcing ply 36 are also arranged substantially parallel to the tire equatorial plane E, like the first reinforcing plies 32 and 33. The above-mentioned first and second reinforcing layers 31, 35
As a whole constitutes a belt reinforcing layer 38 arranged between the belt layer 24 and the tread 29, and the belt reinforcing layer 38 is such that the second reinforcing layer 35 is arranged only at one axial end portion as described above. Therefore, the circumferential rigidity at both axial ends is different from each other, that is, the circumferential rigidity at one axial end is higher than the circumferential rigidity at the other axial end. Since the tire 11 is mounted on the left front wheel of the vehicle as described above, it is mounted outside (when the tire 11 is divided into two regions on the left and right sides of the tire equatorial plane E, the side away from the center in the vehicle width direction). region)
The one end portion in the axial direction, that is, the side having high rigidity in the circumferential direction, is located inside the mounting portion, and the other end portion in the axial direction, that is, the side that has low rigidity in the circumferential direction, is located inside.

Reference numeral 40 denotes an asymmetric pneumatic tire mounted on the right front wheel of the vehicle. This tire 40 is the same as the tire 11 except that the second reinforcing layer 41 is arranged at the other end portion in the axial direction. Have a composition. As a result, in the tire 40, the circumferential rigidity of the other axial end portion is higher than the circumferential rigidity of the one axial end portion. Since the tire 40 is mounted on the right front wheel of the vehicle as described above, the other end in the axial direction on the outer side of the mounting, that is, the side having a high circumferential rigidity, the one end in the axial direction on the inner side of the mounting, that is, the circumferential rigidity. The lower side of is located.

Reference numeral 43 is an asymmetric pneumatic tire mounted on the left rear wheel of the vehicle. The tire 43 comprises a first reinforcing layer 44 composed of a single first reinforcing ply 45, and an axis of the first reinforcing layer 44. One second reinforcing layer 46 that covers one end in the direction is composed of one second reinforcing ply 47, and the other second reinforcing layer 48 that covers the other end in the axial direction of the first reinforcing layer 44 is two. Second reinforcing ply 49
The tire 11 has the same configuration as that of the tire 11, except that As a result, in the tire 43, the circumferential rigidity of the other axial end portion is higher than the circumferential rigidity of the one axial end portion. Since the tire 43 is mounted on the left rear wheel of the vehicle as described above, the axial direction one end portion on the mounting outer side, that is, the side with low circumferential rigidity is mounted on the mounting inner side, contrary to the tires 11, 40. The other end in the axial direction, that is, the side with high circumferential rigidity is located.

Reference numeral 50 denotes an asymmetric pneumatic tire mounted on the right rear wheel of the vehicle. This tire 50 has one second reinforcing layer 51.
Is composed of two second reinforcing plies 52, and the other second reinforcing layer 53 is composed of one second reinforcing ply 54, and has the same structure as the tire 43. As a result, in the tire 50, the circumferential rigidity at one axial end is higher than the circumferential rigidity at the other axial end. And, since the tire 50 is mounted on the right rear wheel of the vehicle as described above,
Contrary to the tires 11 and 40, the other end in the axial direction, that is, the side with low circumferential rigidity is located outside the mounting, and the one end in axial direction, that is, the side with high circumferential rigidity is located inside the mounting.

[0011] And, such set of tires 11, 4
0, 43, 50 are the left front wheel, right front wheel, left rear wheel,
When mounted on the right rear wheel, and when the rear wheel is the drive wheel, the camber angle is given to this rear wheel, so it is high inside the tires 43, 50 mounted on the rear wheel. Ground pressure is generated and a large driving force is exerted,
At this time, the tires 43, 50 mounted on the rear wheels as described above.
By arranging so that the side having a high circumferential rigidity comes to the inside of the mounting, the ground contact pressure inside the mounting of the rear tires 43, 50 is further increased, and a larger driving force can be obtained.
Here, since such an increase in driving force has a favorable effect on steering stability, the steering stability of the tire is further improved. At this time, tire 1 for the front wheels
Since 1 and 40 are arranged in the same manner as the conventional one, that is, the side having high circumferential rigidity is located on the outer side of the mounting, there is no difference from the conventional one. As described above, in the first embodiment, the steering stability can be improved without substantially reducing the riding comfort.

Next, a test example will be described. In this test, first, the left front wheel conventional tire 1 having the same configuration as the tire 11 described above, the right front wheel conventional tire 1 having the same configuration as the tire 40 described above, the tire 43, and the second reinforcing layers 46, 48 described above were used. Left rear wheel conventional tire 1 in which the arrangement side is opposite (the second reinforcing layer 46 is arranged on the other side in the axial direction and the second reinforcing layer 48 is arranged on the one side in the axial direction)
The right rear wheel in which the above-mentioned tire 50 and the second reinforcing layers 51 and 53 are disposed on the opposite side (the second reinforcing layer 51 is disposed on the other side in the axial direction and the second reinforcing layer 53 is disposed on the one side in the axial direction). Conventional tire 1 is prepared, the left front wheel conventional tire 1 is used as the left front wheel, the right front wheel conventional tire 1 is used as the right front wheel, the left rear wheel conventional tire 1 is used as the left rear wheel, and the right rear method is used. The right rear wheel conventional tires 1 were mounted on the wheels (any of the conventional tires 1 had a large circumferential rigidity on the outer side of the mounting). In addition, the tires 11, 40, 43, and 50 as in the above-described embodiment are referred to as test tires 1, and these test tires 1 are the front left wheel, the front right wheel, and the rear left wheel of the vehicle as described above.
It was attached to each of the right rear wheels. Here, the tire size of each tire is for the tire mounted on the front wheel
205/50 ZR17, and all the tires mounted on the rear wheels were 255/40 ZR17. Next, a vehicle equipped with such tires was used to drive on a dry road or a wet road, and the driver's feeling at that time was used to quantify the driving stability. It is the average value obtained by going over and over. The result is
Assuming that the steering stability when dry with the conventional tires 1 attached to the front and rear wheels is 100, and the steering stability when wet is 100, the dry tires with the sample tires 1 attached to the front and rear wheels are The steering stability was 104 and the steering stability when wet was 103. In addition, the vehicle was equipped with the tires as described above and traveled on the winding road, and the ride comfort was quantified by the driver's feeling at that time. It is the calculated average value. The result was 100 when the conventional tire 1 and the test tire 1 were attached to the front and rear wheels, and there was no change.

[0013]

As described above, according to the present invention, the performance, that is, the steering stability, of the set asymmetric pneumatic tire can be further improved.

[Brief description of drawings]

FIG. 1 is a sectional view of an asymmetric pneumatic tire mounted on a front left wheel according to an embodiment of the present invention.

FIG. 2 is a partial cross-sectional view of each tire showing an embodiment of the present invention.

[Explanation of symbols]

17 ... Carcass layer 24 ... Belt layer 29 ... Tread 38 ... Belt reinforcement layer E ... tire equatorial plane

Claims (2)

(57) [Claims] 1. A toroidal carcass layer, a belt layer radially outside the carcass layer, a tread radially outside the belt layer, and a belt layer and the tread. A belt reinforcing layer in which reinforcing cords substantially parallel to the tire equatorial plane are embedded,
An asymmetric pneumatic tire configured to have different circumferential rigidity at both axial ends of the belt reinforcing layer, in which the side with high circumferential rigidity is arranged on the outer side of the front wheel of the vehicle, conversely, A set of asymmetric pneumatic tires, characterized in that the rear wheels are mounted so that the side with higher circumferential rigidity is placed inside the mounting side. 2. A carcass layer having a toroidal shape, and a carcass.
Belt layer disposed radially outside of the belt layer and the belt layer
The tread, which is located radially outward of the
Placed between Red and the inside of the tire is substantially flat on the equatorial plane
A belt reinforcing layer in which a reinforced cord is embedded,
The circumferential rigidity at both axial ends of this belt reinforcement layer
Vehicles with asymmetric pneumatic tires designed to be different from each other
When mounted on both sides, the front wheel of the vehicle has circumferential rigidity on the outer side of the mounting
On the contrary, on the rear wheel, the inner side
Make sure that the side with high circumferential rigidity is placed
A set of asymmetric pneumatic tires characterized by
How to wear.