JP3243321B2 - Automobile tire - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tire for automobiles, and more particularly to a pneumatic radial tire for passenger cars with reduced noise, that is, white noise.

[0002]

2. Description of the Related Art With the maturation of the car life scene, cars are now demanding even more quietness and comfort.
Above all, quietness that can distinguish the subtleties of audio systems is currently strongly demanded by high-performance vehicles around the world. The cabin noise is roughly divided into 3
There are two. The sound of the engine, the sound of the body cutting the wind, and the tire noise. Tire noise is relatively prominent in Japan, where cruising in the speed range is dominant, such as around 100 km / h and the engine speed is also around 2500-3000 rpm. Therefore, in recent years, reduction of tire noise has become a major theme not only in luxury saloons but also in sports cars. Engine sound that has been suppressed by improving accuracy. The wind noise of the body,
It has been gradually reduced due to the evolution of aerodynamic design. In other words, it can be said that tires are the key to lower noise in cars from now on.

The point of noise reduction is how to suppress physical and primitive phenomena in which the tread of the tire hits the road surface at high speed rotation and the air resonates. In order to suppress noise, it is effective to reduce the width of the main groove and to keep the main groove away from the shoulder portion to the shoulder portion. However, this will impair the aquaplaning resistance. From this perspective, FIG.
A radial tire provided with a tread having the rib / block pattern shown in FIG.

[0004]

In the radial tire shown in FIG. 5, side blocks 5 having a sub-groove 4 are arranged on both sides of a center rib 2 having a sub-groove 1 via a main groove 3 in the circumferential direction. , The shoulder blocks 7 are arranged in the circumferential direction via the main groove 6, and each of the blocks 5, 7 is a rib / block pattern in which the length in the circumferential direction is independently changed. The noise reduction is achieved by shifting the source generated when the block edge vibrates, that is, hits the half-wavelength column resonance in 3, 6 in the circumferential direction.

However, in this conventional technique, noise must be reduced only by a change in pitch variation, and when the pitch is increased, the stability and the like are deteriorated, so that there is a limit to noise reduction. The present invention, left and right cell <br/> centers block, left and right side blocks and the left and right sheet <br/> ® by increasing the number in the order of Ruda blocks and circumferentially phase shifting with a large one by the sequence of constitute a basic block pattern, lateral in the basic block pattern
By changing the pitch length of the center block and the left and right side blocks, significant noise reduction without sacrificing wet performance and maneuverability,
The purpose is to be able to expect white noise.

[0006]

According to the present invention, a plurality of circumferential land portions are defined by a plurality of circumferential grooves extending in a circumferential direction, and the circumferential land portions are defined by a plurality of lateral grooves. In order to achieve the above-mentioned object, the following technical means is provided for the automobile tire T provided with the tread 13 which is circumferentially partitioned by 17 to form and arrange at least the center block 18, the side block 19 and the shoulder block 20. Have taken. That is, the present invention, the
Left and right center blocks 18, left and right side blocks 1
9 and the left and right shoulder blocks 20
Multiple left and right center blocks 18, left and right
Side block 19 and left and right shoulder blocks
Increase the number in the order of 20 and shift the phase in the circumferential direction
By arranging the basic block pattern P,
And the left and right sensors in the basic block pattern P.
Each of the tar blocks 18 and the left and right side blocks 1
9 has been changed in the circumferential direction,
The lateral groove at the circumferential end of the basic block pattern P is
Wide, one shoulder is the base point of the other shoulder
Tilt in one direction toward the
In one direction and one in the direction of the other shoulder
In the center, the inazuma-shaped part 17A is
It is characterized by forming (claim
1). 2. The basic block pattern according to claim 1,
In the region P, the lateral groove 17 near its P / 2
Is approximately the same width as the lateral groove 17 in one direction from the shoulder
And inclining in one direction as parallel, inside the side block
It disappears in the middle and the side block has a cracked part 17B
It is recommended to have it (claim 2).

[0007]

When the tire according to the present invention is mounted on an automobile and running, noise generated by the excitation of the half-wavelength column resonance in the vertical groove by the block edge is generated in the shoulder block in the low-speed region. The low frequency generates a high frequency in a high speed region in a side block or the like, and the lateral groove position becomes an appropriate position, thereby dispersing the frequency of each other's noise and generating white noise.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the accompanying drawings. In FIGS. 1 to 4, an automobile tire, specifically, a radial pneumatic tire T of a passenger car or the like is provided with a pair of bead portions 10. And a sidewall portion 11, and both sidewall portions 11 are so-called tubeless having a toroidal cross section by being coupled to a tread portion 13 via a shoulder portion 12. A plurality of treads (parts) 13 extend in the circumferential direction. In the present embodiment, the narrow longitudinal grooves located on the equatorial plane are straight center longitudinal grooves 14, and the wide longitudinal grooves formed at symmetrical positions are straight side longitudinal grooves. A plurality of circumferential land portions are formed by forming straight shoulder vertical grooves 16 with intermediate width grooves formed at the positions symmetrical to the groove 15 and the center vertical groove 14 and at positions outside the side vertical grooves 15, in the embodiment. A pair of center land part, side land part and shoulder land part is formed and the circumferential land part is formed by a lateral groove 1.
Left and right center blocks 1 divided in the circumferential direction by 7
8, left and right side blocks 19 and left and right shoulder blocks 20 are formed and arranged.

The tread pattern is formed by arranging one large basic block pattern P in the circumferential direction. The basic block pattern P is composed of the left and right center blocks 18, the left and right side blocks 19, and the left and right shoulder blocks. > side block 19 of the plurality is and example in a circumferential direction each of the three in the circumferential direction with respect to the two left and right of the center block 18 in the circumferential direction right and left Zehnder blocks 20 and
It is constructed by increasing the number in that order as that in the circumferential direction four lateral shoulder blocks 20 are arranged by shifting the circumferential direction of the phase.

[0010] In addition, the left in the basic block pattern P
Each of the respective left and right side blocks 19 on the right of the center block 18 and the circumferential length thereof is varied individually (differently), respectively the circumferential length also of the right and left of the shoulder block 20 in the embodiment Each variation is different (different). Here, various variations are possible by a pitch variation for each pitch (basic block pattern P) and a variation in individual pitch length within the basic block pattern P. A noise reduction system that disperses the frequency of the noise and generates white noise.

In particular, pitch length and groove width are not limited with respect to noise, but the block pattern is formed with the best balance in consideration of wet performance and operability. Lateral grooves in the circumferential direction end portions of the basic block pattern P 17
Has a wider the groove width, in the lateral grooves 17 is one of the shoulder Example inclined in one direction toward the other shoulder to the right shoulder as a base point, inclined in opposite direction in the center portion and towards the other shoulder Tilt in one direction,
Here, the center portion is formed as a chin-shaped portion 17A.

Further, in the basic block pattern P, the lateral groove 17 in the vicinity of the position P / 2 is inclined in one direction with the shoulder as a starting point, having substantially the same width and being parallel to the lateral groove 17 in one direction. Here, the side block has a concave portion 17B in the side block, and the lateral groove 17 near P / 4 has a narrow width and disappears in the middle of the center block. Has a narrow crevice 17C. Note that the above illustrated example is one embodiment of the present invention, and the vertical grooves may be formed to have the same width, have a so-called zigzag shape, or a combination of a straight shape and a zigzag shape. also not good.

[0013]

As described above, the present invention has various variations in the tread block pattern, so that the noise frequency can be dispersed and white noise can be obtained, and the wet performance and the controllability are impaired. Nothing. Incidentally, an actual vehicle test was performed on a radial tire having a tire size of 205 / 60R15. FIG.
In the pattern according to the present invention assuming that the noise reduction index of the tread pattern shown in FIG.
Remarkable white noise was achieved.

[Brief description of the drawings]

FIG. 1 shows an embodiment of the present invention, wherein (A) is a perspective view,
(B) is a development plan view of a main part.

FIG. 2 is a front view showing an embodiment of the present invention.

FIG. 3 is an enlarged front view of a part of FIG. 2;

FIG. 4 is a sectional view taken along line CC of FIG. 3;

FIG. 5 is a developed plan view of a main part of a conventional example.

[Explanation of symbols]

 T tire 13 Tread 14 Vertical groove 15 Vertical groove 16 Vertical groove 17 Horizontal groove 18 Center block 19 Side block 20 Shoulder block P Basic block pattern

Claims (2)

(57) [Claims] 1. A plurality of circumferential grooves extending in a circumferential direction.
(15) A plurality of circumferential land portions are defined by (16).
And the circumferential land portion is connected to a plurality of lateral grooves (17).
More circumferentially divided at least the center block (1
8), side block (19) and shoulder block
Treads (13) arranged to form
The left and right center blocks (18) and the left and right side
Lock (19) and left and right shoulder blocks (2
Each of 0) is a plurality in the circumferential direction and the left and right centers
Block (18), left and right side blocks (19) and
And the number of shoulder blocks (20) in the order of
By increasing the number and arranging the phase in the circumferential direction, the basic
Lock pattern (P)
Left and right center blocks in the lock pattern (P)
(18) and left and right side blocks (19)
Each circumferential length has been changed and the basic
The lateral groove at the circumferential end of the block pattern (P)
Wide, one shoulder is the base point of the other shoulder
Tilt in one direction toward the
In one direction and one in the direction of the other shoulder
In the center part, the inazuma-shaped part (17
An automobile tire, wherein A) is formed. 2. The method according to claim 1, wherein the basic block pattern (P) is
And the horizontal groove (17) near (P / 2) is
With the same width as the lateral groove (17) in one direction starting from the shoulder
And inclining in one direction as parallel, inside the side block
The side block disappears, and the side block
B).
Tires for moving vehicles.