JPH11245626A - High performance pneumatic tire for automobile - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate the delay of handle responsiveness easy to be generated when tires are installed with inward inclination by positioning the center line of a rib in the central circumferential direction with a displacement at a specified value from the tire equatorial plane in the axial direction of the tire. SOLUTION: Tires are installed in an expanded stride shape at a vehicle while inclined inside at 1.5 degree of camber angle θ. A tread is formed with a tread pattern provided with a pair of central circumferential grooves 1, 2 in right and left arranged in both sides of the tire equatorial plane and extended in the tire circumferential direction and central circumferential ribs 3 arranged inside of the pair of central circumferential grooves 1, 2 in right and left and extended in the tire circumferential direction. At this stage, the central circumferential ribs 3 are arranged asymmetry in right tan left so that the center line C of the central circumferential ribs 3 are positioned with a displacement from the tire equatorial plane E by a distance (d) in the tire axial direction, and the tire is installed so that a side thereof provided with the eccentrically positioned central circumferential rib 3 is arranged inside of the vehicle. A distance D is computed with R.tanθ.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pneumatic tire, and more particularly, to a bead core provided on a pair of right and left beads, and extending from a crown to both beads via both side portions. A carcass ply wound around a core and moored to a bead portion, a belt disposed radially outward of a crown portion of the carcass ply, and a tread disposed radially outward of the belt. On the tread, a pair of left and right central circumferential grooves extending on the tire circumferential direction or substantially circumferential direction, which are disposed on the left and right sides of the tire equatorial plane, and are disposed adjacent to the central circumferential groove. A high performance pneumatic tie for a passenger car, which is formed with a tread pattern having a central circumferential rib extending in the tire circumferential direction, and which is mounted on the vehicle in a shape of a letter C inwardly inclined at a camber angle θ. It relates.

[0002]

2. Description of the Related Art Generally, pneumatic tires for passenger cars are not mounted straight in the vertical direction when mounted on the vehicle, but are usually mounted at a small angle in the vertical direction and inclined. There are many. This angle is called a camber angle or a camber angle. In a so-called high-performance sports car, it is usual that a camber angle of about 1 to 3 degrees is provided and the car is inclined inward and mounted on the vehicle in a C-shape. . However, the conventional pneumatic tire has a camber angle of about 1 to 3 degrees as described above, and the tread pattern is designed without considering that the tire is inwardly inclined and mounted on a vehicle. It had been. As a result, in the conventional pneumatic tire having the tread pattern as described above, the central circumferential rib is disposed at the center of the tread, in other words, the center line of the central circumferential rib is located on the tire equatorial plane. The central circumferential ribs are arranged symmetrically.

[0003]

As described above, a pneumatic tire having a conventional tread pattern having a central circumferential rib disposed at the center of the tread has a camber angle of about 1 to 3 degrees. If the vehicle is mounted in a V-shape with a slanted inward, a slight time lag may occur in the steering wheel response at the beginning of rudder turning, and the driver may feel dissatisfied with the feeling of delay. .

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned disadvantages of the prior art, and to provide a pair of left and right tire circumferentially or substantially circumferentially disposed on both left and right sides of the tire equatorial plane. A pneumatic tire formed with a tread pattern having a central circumferential groove and a central circumferential rib extending in the tire circumferential direction and disposed adjacent to the central circumferential groove. An object of the present invention is to provide a pneumatic radial tire for a high-mobility passenger car, which eliminates a delay in steering wheel response performance, which is likely to occur when the vehicle is mounted on a vehicle in a V-shape with an inclination.

[0005]

In order to achieve the above object, a pneumatic tire according to the present invention comprises a bead core provided on a pair of right and left beads, and a bead via a crown portion and both sidewalls. A carcass ply wound around the bead core and moored to the bead portion, and a belt and a tread arranged radially outside the crown portion of the carcass ply, and the tread includes: Located on the left and right sides of the tire equatorial plane,
A pair of left and right central circumferential grooves extending in the tire circumferential direction or substantially in the circumferential direction; and a central circumferential rib extending in the tire circumferential direction and disposed inside the pair of left and right central circumferential grooves. A pneumatic tire having an outer diameter of 2R, which is formed on a vehicle and inclined inward at a camber angle θ and has a tread pattern with a camber angle θ, (1) the center line of the central circumferential rib Is arranged asymmetrically in the tire axial direction so as to deviate from the tire equatorial plane by R · tan θ, and (2) such that the unevenly distributed side of the central circumferential rib is located inside the vehicle. A high-performance pneumatic tire for a passenger car, which is mounted on a vehicle.

A pair of left and right central circumferential grooves are disposed on the left and right sides of the tire equatorial plane, and a central circumferential rib is disposed adjacent to the inside of the pair of right and left central circumferential grooves. In the conventional tire, a central circumferential rib having a width of about 20 to 30 mm is arranged at the center of the tread. In other words, the central circumferential rib is positioned so that the center line of the central circumferential rib is located on the tire equatorial plane. The ribs were arranged symmetrically. When a conventional pneumatic tire having a tread pattern as described above is mounted on a vehicle with a camber angle of about 1 to 3 degrees and inclined inward, the ground contact center becomes the tire equator. It deviates from the surface by about 10 to 20 mm, and the grounding center is located not in the rib but in the groove. As a result, it has been found that a slight time difference occurs in the steering wheel response performance at the beginning of turning the rudder, and the driver may feel dissatisfied with the feeling of being late.

The pneumatic tire of the present invention has the above-described structure. In particular, the tread includes left and right tires disposed on the right and left sides of the tire equatorial plane and extending in the tire circumferential direction or substantially in the circumferential direction. A tread pattern having a pair of central circumferential grooves and central circumferential ribs extending in the tire circumferential direction and arranged inside the pair of left and right central circumferential grooves is formed, and a camber angle θ is formed. In a pneumatic tire having an outer diameter of 2R, which is attached to the vehicle in a shape of a letter inclined inward at (1), (1) the center line of the central circumferential rib is R · tanθ from the tire equatorial plane in the tire axial direction The central circumferential ribs are arranged asymmetrically so as to be shifted, (2)
The center circumferential rib is mounted on the vehicle such that the unevenly distributed side is positioned inside the vehicle, so that when the tire is attached to the camber angle and inclined inward and mounted on the vehicle in a C-shape, the ground contact center is formed. Are located on the uneven ribs without being located in the groove. As a result, even at the beginning of turning the rudder, there is no time difference in the steering wheel response performance, and the feeling of dissatisfaction of the conventional feeling of delay is eliminated.

[0008]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a high-performance pneumatic radial vehicle passenger car according to an embodiment of the present invention;
A tire and a conventional high performance pneumatic radial tire for a passenger car will be described. Each tire size is 245 / 45ZR17.

FIG. 1 is a partially enlarged schematic view of a tread pattern of a tire according to an embodiment of the present invention. The tire according to the embodiment includes a bead core (not shown) provided on a pair of left and right bead portions, and extends from the crown portion to both bead portions via both sidewall portions, and is wound around the bead core to form a bead portion. A high-performance passenger car including a carcass ply (not shown) composed of moored radial cords, and a belt (not shown) and a tread (not shown) arranged radially outside the crown portion of the carcass ply. Pneumatic radial tire with camber angle θ =
Tilt inward at 1.5 degrees, attached to the vehicle in a C shape,
The outer diameter is 2R = 326 mm. As shown in FIG. 1, the tread has a pair of left and right central circumferential grooves 1 and 2 extending in the circumferential direction of the tire and arranged on both left and right sides of the tire equatorial plane E, and a pair of right and left central circumferential grooves. A tread pattern having a central circumferential rib 3 extending in the tire circumferential direction, which is disposed adjacent to the inside of the directional grooves 1 and 2, is formed. In the tire according to the embodiment, the center circumferential ribs 3 are arranged asymmetrically so that the center line C of the center circumferential rib 3 is shifted from the tire equatorial plane E by a distance d in the tire axial direction. 3 is mounted on the vehicle such that the unevenly distributed side is located inside the vehicle. This distance d is Rtan
is calculated by θ, R = 163 mm and θ = 1.5 degrees, so that d = 8.5 mm.

[0010] The conventional tire has the above-mentioned construction except that the center line C of the center circumferential rib 3 is located on the tire equatorial plane E and the center circumferential rib 3 is symmetrically arranged. It is almost the same as the tire of Example 1.

The tire of the above embodiment according to the present invention and the tire of the prior art are assembled on a rim 9J-17, filled with an internal pressure of 2.4 kg / cm ² , mounted on a test vehicle, and mounted on a high-speed straight road. A feeling evaluation test was conducted by a test driver on a winding road including running and curved road running from low speed to high speed. The evaluation items are straight running performance including small steering angle response performance, lane change performance, cornering performance, and their overall performance.
As a result of this evaluation test, the straight running performance, the lane change performance, and the cornering performance were 6.0, 6.0, and 6.5 in the above-described conventional tires when displayed on a scale of 10 out of 10, whereas the actual running performance was 6.0, 6.5, and 6.5. The tires of the above examples according to the invention showed excellent results at 6.5, 7.5 and 7.0. Further, the overall performance of these tires was 6.0 in the above-mentioned conventional example, whereas the tire of the above-mentioned example according to the present invention was 7.25, showing an extremely excellent result.

[0012]

From the above results, it can be seen that the present invention can provide a pneumatic radial tire for a passenger car which is excellent in straight running performance including small steering angle response performance, lane change performance, cornering performance and overall performance thereof. I understand.

[Brief description of the drawings]

FIG. 1 is a partially enlarged front view of a tread pattern of a tire according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Central circumferential groove 2 Central circumferential groove 3 Central circumferential rib C Center line of central circumferential rib 3 E Tire equatorial plane

Claims (1)

[Claims] 1. A bead core provided on a pair of left and right bead portions, and a carcass extending from the crown portion to both bead portions via both side wall portions, wound around the bead core and moored to the bead portions. A ply, a belt and a tread arranged radially outward of a crown portion of the carcass ply, and the tread has a tire circumferential direction or substantially arranged on both left and right sides of the tire equatorial plane. A pair of left and right central circumferential grooves extending in the circumferential direction, and disposed adjacent to the inside of the pair of left and right central circumferential grooves;
In a pneumatic tire having an outer diameter of 2R, a tread pattern having a central circumferential rib extending in a tire circumferential direction is formed, and is mounted on a vehicle at a camber angle θ and inclined inwardly in a C shape. 1) The central circumferential ribs are arranged asymmetrically so that the center line of the central circumferential ribs is shifted from the equatorial plane of the tire by R · tan θ in the tire axial direction. A high performance pneumatic tire for a passenger car, wherein the tire is mounted on a vehicle such that the unevenly distributed side is located inside the vehicle.