JP3426289B2 - High performance flat pneumatic radial tire - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [0001] BACKGROUND OF THE INVENTION The present invention relates to a high performance flat pneumatic
With regard to dial tires, especially those exceeding 200 km / h
Equipped on vehicles (mainly passenger cars) that are also used for high-speed driving
And the required performance is complete, especially high-speed durability
When turning while maintaining a high level of performance
Further improvements in road surface grip (gripability)
It is intended to propose a tire of this type. [0002] High-performance pneumatics mounted on high-speed running vehicles
Tires usually have an aspect ratio of 0.6 or less, and more recently 0.35 or less.
Practically up to extremely low things like below, here the vehicle speed
Must withstand high speeds of over 300 km / h
It is said. [0003] This is because even in the highway network,
As the construction of dedicated roads is widespread, automobiles
In response to the remarkable progress of high output and high performance of
Emergency requests can be dealt with without delay
This is because the establishment of a posture is desired. [0004] 2. Description of the Related Art Flat air-filled laminators for this kind of use
Dial tires are made of radiators such as rayon and polyester.
A toroidal carcass consisting of
For reinforcement of the body, add the carcass crown
Around the plane containing the center circumference of the carcass
With a very small angle, that is, an inclined arrangement of 20 to 35 °, practically no stretching
Long, usually from steel filament cord
Belt having at least two layers of cord cross laminated structure
And the outer periphery of the belt is further substantially
A heat-shrinkable cord covering the entire width of the belt in a parallel arrangement
For example, a single layer of spiral wound nylon cord
Or a two-layer cap, sometimes with this cap
By a similar spiral winding around the perimeter of both sides of the
Along with 1-3 layers, as tread reinforcement
The tread portion has multiple
It has a number of outer circumferential main grooves.2As shown in
Compared to more general, so-called general-purpose pneumatic tires,
It is characterized by remarkable reinforcement of armor inside the tread as a body
is there. [0005] SUMMARY OF THE INVENTION A conventional flat pneumatic lane
An example of reinforcing the tread required for high performance tires
As mentioned above, the belt and cap and sometimes
Has a low aspect ratio, in addition to advanced lamination such as layers
That is, the side wall height is low and the momentum
The rigidity of the tire as a whole is
The load acting on the tire when rolling
bigCousinEspecially when turning, the tread grips
Problem with reduced turning performance due to reduced power
Is pointed out. [0006] The inventors have studied this point.
As a result, the decrease in the grip force is caused in the tread contact area.
The contact pressure becomes extremely uneven during turning, and
Regarding the unevenness of the tread under the above strengthening of the tread,
Generated near the midpoint of the tread half width (so-called 1/4 point)
It was found to be due to buckling. Here, the buckling is performed by grounding the tread.
Acts on the outer edge of the turn when the tire is turning on the surface
The in-plane compressive stress based on the external force
Large deformation with out-of-plane displacement occurs near the above 1/4 point.
Large deformation of the tread with the tread reinforcement layer described above
Raised so that the inner surface of the crown bulges inward,
The tread surface appears to be locally depressed
You. Therefore, a tray in which such a depression does not appear.
High-performance flat space
Deterioration of clipping property during turning of a pneumatic tire
Was advantageously avoided without adversely affecting high-speed durability.
Giving high performance flat pneumatic radial tires
It is an object of the invention. [0009] SUMMARY OF THE INVENTION The present invention provides a radial arrangement.
Body with toroidal carcass consisting of cord plies
Around the carcass as reinforcement,
The inclination arrangement at a relatively small angle with respect to the plane including the center circumference of
At least two layers of substantially inextensible cords
Belt with cord cross lamination and outer circumference of this belt
In addition, the width of the belt is substantially
At least one layer comprising a heat-shrinkable cord surrounding the
And a cap for reinforcing the tread part.
A plurality of outer peripheral main grooves spaced in the width direction
Pneumatic radial tire with an aspect ratio of 0.6 or less
And between the belt and the cap with respect to the above plane
At an angle that does not match the inclined arrangement of the belt cord at 40 °
At least one layer of non-metallic cords
The midpoint of the tread half width in cooperation with the belt crossing cord
A tension member that resists buckling in the vicinity
And 70-95% of the width of the adjacent belt
High-performance flat air characterized by being interposed
It is a radial tire containing. Here, on both sides of the cap, their perimeters
By a spiral winding similar to the cap surrounding
1 ~ 3 layers, end separation of belt
Needless to say, it can be added to prevent
If at least one belt end of the layer away from
Inner edge is outside the 1/4 point of the tread and the outer periphery of the tread
Separate from just below the groove bottom of the main groove, and there is a layer remaining
This is also recommended to be located just below the groove bottom
New FIG. 1 shows a high-performance flat according to the present invention.
The main part of the pneumatic radial tire is shown in the cross section of the left half,
In the figure, 1 is a rayon code (1650 D / 2) 1 in this example._-1, 1
_-2, Two-ply toroid used in radial arrangement
Carcass, 2 surrounds carcass 1
In this example, a plane p including the central circumference of the carcass is
Steel cords with a 25 mm inclined arrangement (wire diameter 0.23 mm
1 × 5 structure) 2_-1, 2 _-2, The cross-lamination of two layers
Belt, 3 is a non-metallic cord, in this example Kevlar
(Aromatic polyamide) code (1500 D / 3)
At the inclination of 31 ° to the cord 2 of the belt 2_-2Intersect with
With the tension member, the adjacent code 2_-2No
Belt 2 with an arrangement width equivalent to 87% of the belt width W,
The cap 4 is interposed between the next cap 4 and the cap 4.
In this example, the outer circumference of the belt 2 covers the entire width.
Nylon cord (1260 D / 2) 4_-1, 4_-2, Each of 5
Spiral using a rubber-coated ribbon aligned with the book
And 5 is on both sides of the cap 4.
In each area, nylon cord (1260 D / 2) 5_-1, 5
_-2Cord 5 using a similar ribbon_-1Compared to
And 5_-2Is two layers spirally wound with a narrower width
Carcass 1 is a layer to be laminated
And the belt 2 and the cap 4 and the layer 5
It shall be provided as red part reinforcement. The tread portion T has an interval in the width direction.
In this example, the layer 5 has a plurality of outer main grooves 6.
Inner end of the arrangement interposing the outer peripheral main groove 6 near the side end of the red portion T
Shall be provided. In this invention, Kevlar
The tension member 3 who raised the example of using the
High quality plastics such as ester (PET), rayon and nylon
Juras code may be used. [0013] According to the present invention, the above-described body reinforcement and tread reinforcement are provided.
And the groove arrangement of the tread portion T,
Performance requirements for flat pneumatic radial tires
In addition to following the usual conventions for adding, especially when turning
In order to improve the grip performance of the tread part T in
Cross cord of belt 2 between belt 2 and cap 4
2_-1, 2_-2Wins near the midpoint of the tread half width in cooperation with
Through tension member 3 that resists buckling
There is peculiarity in the point of setting. This tension member has already been read
High modulus non-metal optimized for sea-Kevlar cord
Intersect the code with the plane containing the central circumference of the carcass
Is between 15 and 40 ゜, and the cord 2 of belt 2_-2And tilt arrangement
By adopting an inclined arrangement that does not work, the cord of belt 2
2_-1, 2_-2To form a triangular network with
Helps to significantly increase the bending stiffness of the belt 2
In addition, tension is applied to the plane including the center circumference of the carcass.
Bending if the inclination arrangement of the cord of member 3 is less than 15 mm
This does not help to increase the rigidity, and the same
This means that the out-of-plane displacement caused by the buckling
Maximum length near the midpoint of the ground length and tread half width
This displacement occurs as if
To form a more advantageous triangular network structure
And here is the adjacent code 2 of the belt 2 _-2The angle difference from
Is preferably about 10 °. The arrangement width w of the tension member 3 is
Code 2_-2Narrower than 70% of the belt width WWhenTread half width
Effect of suppressing out-of-plane displacement near the midpoint of
On the other hand, if it is wider than 95%, the end separation of belt 2
This arrangement width w is limited due to adverse effects on the application
That's why. [0016] [Example] A prototype tire of size 285/40 ZR17 is shown in FIG.
And compared with the conventional tire shown in FIG.
Fig. 3 shows the test results of the contact pressure distribution on the tread.
did. Here, the reinforcing structure of the conventional tire shown in FIG.
According to all points, the common configuration with the prototype tire is
Corresponding numbers are assigned. The difference from the prototype tire is
Whether there is a tension member. FIG. 3 shows the distribution of the contact pressure in the width direction of the tread portion T.
Is a broken line for the conventional tire, while
For the work tire, use Kevlar cord for tension member 3
Case of using a solid line and nylon cord
Were compared with a dashed line. The test conditions are rim size 10J × 18 and wheels
Assembling, internal pressure 2.5kgf / cm^Two, Speed 30km / h, load 500kg^WC
A is 0 ° and SA is set to 8 °.
Is the local contact pressure near the midpoint (1/4 point) of the tread half width
Drop and consequently significant contact at the tread edge
Despite the rise in ground pressure, the prototype tire
Also, the degree of contact pressure drop near the 1/4
It has been found that the rise in the contact pressure at the end of the pad is also suppressed. Next, the Kevlar code is transferred to the tension member.
The internal pressure of the test tire used in 3 and the conventional tire is 2.
5kgf / cm^Two, Load 500 kg^W10km every 20 minutes after adding
Table 1 compares the speed at which the speed increases to
The results are shown in the index notation, with the grade of YA as 100. Table
1, the difference Δ between the maximum value and the minimum value of the ground pressure shown in FIG.
P and ΔP 'are similarly indicated by exponents, and a radius of 50
Feeling of an actual car when turning on a circuit surface of m
The test findings are also shown. [0020] [Table 1][0021] According to the present invention, a high-performance flat tire mounted on a high-speed traveling vehicle.
Grinding of the tread during turning of the dial tire
Advantageous reduction in tapping force without deterioration of high-speed durability
To achieve significant improvement in stable turning performance
it can.

[Brief description of the drawings] FIG. 1 is a cross-sectional view of a tire according to the present invention. FIG. 2 is a partial sectional view of a conventional tire. FIG. 3 is a contact pressure distribution comparison graph. [Explanation of symbols] 1 Carcass 2 belt 3 tension members 4 caps

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-5-58112 (JP, A) JP-A-1-175505 (JP, A) JP-A-5-131810 (JP, A) JP-A-3-131 82604 (JP, A) (58) Field surveyed (Int. Cl. ⁷ , DB name) B60C 9/18-9/22

Claims (1)

(57) [Claims 1] A toroidal carcass composed of plies of a radial arrangement cord is used as a body reinforcement, and is compared with a plane surrounding the carcass and including the center circumference of the carcass. A belt having at least two layers of cord cross-layers of substantially non-extensible cords having a slanted arrangement at an extremely small angle, and an outer periphery of the belt further arranged in a direction substantially parallel to the plane to reduce the overall width of the belt. At least one cap made of a heat-shrinkable cord surrounding the cover as a reinforcement for the tread portion, the tread portion having a plurality of outer peripheral main grooves spaced in the width direction, and having an aspect ratio of 0.6. For the following pneumatic radial tires, a non-metallic core with a slanted arrangement between the belt and the cap at an angle of 15 to 40 ° with respect to the above plane at an angle that does not match the inclined arrangement of the belt cord A tension member consisting of at least one layer of belts and cooperating with the belt crossing cord to resist buckling near the midpoint of the half width of the tread with an arrangement width of 70 to 95% of the width of the adjacent belt. A high-performance flat pneumatic radial tire characterized by being provided.