JP3445679B2 - Pneumatic radial tire - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention allows the tread rubber portion to be freely attached and detached from the remaining tire base body.
For example, the present invention relates to a pneumatic radial tire that can inexpensively supply various tread patterns according to the purpose of use and the like, and can repeatedly use a tire base body when the tread rubber is worn away, which is useful for effective use of resources.

[0002]

2. Description of the Related Art In recent years, in a tire having a radial structure in which the strength life of the carcass is higher than the wear life of the tire,
From the viewpoint of effective use of resources, some tires are being rehabilitated by replacing worn tread rubber and reusing it.

Conventionally, a tire is one in which a tread rubber and the remaining tire base are integrally bonded by vulcanization. Therefore, in tire retreading, a base tire obtained by removing the tread rubber by buff cutting or the like is used. An unvulcanized tread rubber material is attached, and after that, it is re-integrated by vulcanization molding in a mold.

[0004]

However, as described above, the cost for retreading the tire is high because it requires many work steps such as buff cutting, rubber sticking, vulcanization and molding in the mold. There is a problem. Therefore, for relatively inexpensive tires, such as tires for passenger cars and tires for light trucks, which account for approximately 60% or more of the total number of tires, the price difference from new tires becomes extremely small, which makes it difficult to economically implement them. It is not possible to achieve effective utilization of resources.

On the other hand, in the case of this type of tire, in order to sufficiently exhibit the running performance of a vehicle having high performance and high output, for example, for wet, dry, off-road,
Tread patterns with various performances are provided according to the purpose of use, such as for ice and snowy roads, and the road surface environment. As a result, the number and type of tires increase, increasing the economic burden on the user, and further hindering the effective use of resources such as increasing the number of unused tires and unnecessary tires.

The present invention is based on the fact that the tread rubber portion can be freely attached and detached from the tire base body.
It is an object of the present invention to provide a pneumatic radial tire that simplifies the reuse of tires, can supply various tread patterns at low cost, and can solve the above problems.

[0007]

The invention according to claim 1 of the present invention has a vulcanized annular tread ring and a vulcanized tread bottom which forms a tread portion of a tire by attaching the tread ring to the outer peripheral surface. A tire carcass having a carcass cord of a radial arrangement and being folded back around the bead core of the bead part from the tread bottom part to the sidewall part, and forming the outer peripheral surface of the tread bottom part. And a support layer formed of a rubber composition having a rubber thickness of 0.5 to 5 mm, the tread ring is a belt layer in which belt cords are arranged at an angle of 30 degrees or less with respect to the tire equator. In addition, when the tire base body is integrally connected with the tire base body by expansion of the tire base body in the radial direction due to the internal pressure filling. Moni, the axially outer end of said tread ring, Rutoto provided lift preventing reinforcing layer to prevent the floating due to the centrifugal force caused by the tire rotation of the outer end
In fact, this lift prevention reinforcement layer is used for the tread ring.
One cord provided on the outer side in the radial direction of the belt layer
Or several cords were aligned and embedded in topping rubber
A belt-shaped ply spirally wound at a small angle to the tire equator.
At least one more jointless band
A pneumatic radial tire characterized by being an extension of a layer .

The invention according to claim 2 is a vulcanized ring.
-Shaped tread ring and this tread ring on the outer peripheral surface
The tread that forms the tread part of the tire by installing
A vulcanized tire base having a bottom,
For the ear base, slide the sidewall from the bottom of the tread.
It is folded around the bead core of the bead part and
A carcass having a carcass cord of a dial arrangement, and
The outer peripheral surface of the tread bottom is formed and the rubber thickness is 0.
A support layer formed of a rubber composition of 5 to 5 mm
Meanwhile, the tread ring ties the belt cord.
A belt layer arranged at an angle of 30 degrees or less with respect to the equator
And in the radial direction of the tire base due to internal pressure filling
When it is integrally connected to the tire base due to outward expansion
Together, at the tire axial outer end of the tread ring,
Lifting due to centrifugal force due to tire rotation at this outer edge
Provided with a lift preventing reinforcing layer to prevent, this lift
The preventive / reinforcing layer is a pneumatic radial tire characterized by comprising a cloth-like body using organic fibers .

The lift prevention reinforcing layer may be formed by an extension of the jointless band layer.
Further, it may be formed from a cloth-like body using organic fibers.

The invention according to claim 3 is the tire base body.
On the outside of the carcass in the radial direction,
Reinforced layer consisting of more than one ply arranged in the direction
It is characterized by that.

[0011]

The tire is divided into a tire base having a carcass and a tread ring for forming a tread on the outside thereof,
Each of these is configured as a vulcanized independent body. The tire base body expands like a rubber ball by the filling internal pressure, and the tread ring includes a belt layer in which belt cords are arranged at an angle of 30 degrees or less with respect to the tire equator. Therefore, it is not stretched in the radial direction. Therefore, a strong pressure contact force is generated between the tread bottom portion and the tread ring due to the filling internal pressure, whereby both are firmly and integrally connected without causing slippage, and,
Since the tread ring is provided with a belt layer and preferably a jointless band layer, it is possible to prevent the tire base body from being excessively changed in shape and to prevent variations in tire performance due to the incorporation of the tread ring. It can be suppressed, and the steering performance similar to that of conventional tires can be exhibited. Further, lifting of the outer end portion of the tread ring in the axial direction of the tire due to centrifugal force caused by rotation of the tire during traveling can be prevented by the lift prevention reinforcing layer provided at the outer end portion. The lift prevention reinforcement layer can be easily formed by the extension of the jointless band layer, and lifting can be prevented by a cloth-like body using organic fibers. Furthermore, by providing a reinforcing layer composed of one or more plies in which cords are arranged in the tire axial direction on the outside of the carcass in the radial direction of the tire base, the carcass in the tread portion can be reinforced more reliably, and running safety is maintained. sell.

On the other hand, in the tire of the present application, the tread ring can be easily removed from the tire base by discharging the filling internal pressure. Therefore, for example, when the tread surface is worn or when traveling on an ice / snow road surface, the user can freely replace the new tread ring without wear and the tread ring having the tread pattern for the ice / snow road. As a result, wasteful disposal of the tire itself, unnecessary increase in types, etc. can be prevented, resources can be effectively utilized, and tread patterns with various performances can be provided at low cost.

Moreover, since the tire base body to be reused can be managed by the user himself, the fatigue damage state of the carcass can be grasped, the reliability can be improved as compared with the conventional tire rehabilitation, and the repeated use is possible.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 shows a pneumatic radial tire 1 (hereinafter referred to as tire 1
Shows a meridional section of a tire in a state where it is assembled to a standard rim R and filled with standard internal pressure.
Is a flatness ratio of 8 which is the ratio of tire height to tire width.
It is formed as a radial tire for passenger cars of 0% or less.

In FIG. 1, a tire 1 includes a pair of bead portions 3 and 3 each having a bead core 2 and 2, sidewall portions 4 and 4 extending outward from the respective bead portions 3 and 3 in the tire radial direction, and And a tread portion 5 in which the outer ends of the sidewall portions 4 and 4 are joined together and a tread pattern P is recessed on the outer peripheral surface.

Further, the tire 1 is, as shown enlarged in FIG.
The tread ring 6 and the tire base 7, which are the remaining portion of the tread ring 6 and the radial outside of the tread portion 5, are formed as vulcanized independent bodies.

The tire base body 7 has a toroidal shape in which the outer ends of the sidewall portions 4 and 4 extending from the bead portions 3 and 3 are joined by a tread bottom portion 9 having a small thickness, and the outer peripheral surface of the tread bottom portion 9 is formed. By detachably attaching the tread ring 6 on 9S, the tread bottom portion 9 and the tread ring 6 cooperate to form the tread portion 5.

The tire base 7 has a tread bottom 9
A carcass 10 which is folded back from the inside to the outside around the bead cores 2 and 2 through the side wall portions 4 and 4 is provided, and the side wall portions 4 and 4 are provided on the outer side in the radial direction of the carcass 10. Sidewall rubber 4 to be formed
A support layer 12 that spans between the radially outer ends of A and 4A and that forms the outer peripheral surface 9S of the tread bottom 9 is provided.

The carcass 10 is formed by one or more carcass plies 10A in which the carcass cords are radially or semi-radially arranged at an angle of 70 to 90 degrees with respect to the tire equator C, and in this example, one carcass ply 10A. A polyester fiber cord is used as. Other than the carcass cords, organic fiber cords such as nylon, rayon and aromatic polyamide, and metal fiber cords such as steel may be used depending on the required tire performance.

A bead apex 11 made of hard rubber extending from the bead core 2 outward in the radial direction of the tire and made of a hard rubber having a substantially triangular shape is interposed between the main body of the carcass 10 and the folded-back portion. Reinforces the portion 4 to improve the lateral rigidity of the tire.

The outer peripheral surface 9S of the tread bottom 9 extends in a direction substantially parallel to the carcass 10 and slightly outward in the radial direction, and both ends thereof are sidewalls formed by the sidewall rubbers 4A and 4A. It smoothly connects to the outer surface.

The outer peripheral surface 9S of the tread bottom 9 is required to be completely covered without exposing the carcass cord in order to prevent water or the like from entering the carcass cord and to enhance the airtightness of the tire. Therefore, in this example, in order to further prevent damage to the carcass due to rubbing with the tread ring 6, the support layer 12 that supports the tread ring 6 is formed outside the carcass 10, and the outer surface of the support layer 12 is The outer peripheral surface 9S is configured.

The support layer 12 has a rubber thickness of 0.5 to 5 mm,
More preferably, it is composed of a rubber composition of 2 to 4 mm, and its hardness is 60 to 96 degrees of JIS A hardness and its elastic modulus is 20 to
It is preferably in the range of 50 kgf / cm ² .

A reinforcing layer 14 made of an organic material such as nylon or polyester can be provided outside the carcass 10 in the radial direction and inside the support layer 12. The reinforcing layer 14 is composed of one ply in which cords are arranged in the same direction as the carcass cord or two plies in which cords are arranged at an angle of 30 ° to 90 ° with respect to the tire equator C. Can be reinforced by the tread bottom portion 9 of the tire base 7 to improve puncture resistance and the like.

The reinforcing layer 14 can also be formed by using one or more plies in which cords are arranged substantially in the axial direction of the tire. In this case, since the cord of the ply forming the reinforcing layer can be oriented substantially parallel to the carcass cord, the lateral rigidity of the tread bottom 9 of the tire base 7 can be increased.

The tread ring 6 is a vulcanized annular body having a tread pattern P formed of a tread groove G formed on the outer peripheral surface, and the outer peripheral surface 9S of the tread bottom 9 is formed.
The inner peripheral surface 6 so that it can be attached tightly and tightly
S is formed by a curved surface along the outer peripheral surface 9S. That is, the inner peripheral surface 6S has outwardly facing surfaces 9S1 and 9S at its outer end portion in the axial direction of the tire, the outward facing surfaces 9S1 and 9S facing both sides in the axial direction of the tire.
1, the sloping wing surface portions 6S1 and 6S1 are provided so that the tread ring 6 is restrained from being displaced in the tire axial direction.

The tread ring 6 includes a belt layer 1
5 is provided, and in the present embodiment, a jointless band layer 16 is disposed on the outer side in the radial direction of the belt layer 15 in order to prevent lifting of the belt layer 15 during high speed running.

At least one belt layer 15 is provided,
In this example, the inner and outer two belt plies 15A and 15B are formed. In each of the belt plies 15A and 15B, high-strength belt cords are arranged at a shallow angle of 30 degrees or less with respect to the tire equator C, and the belt cords cross each other. This increases the rigidity of the tread ring 6.

Further, the belt layer 15 has an arc shape having a center on the tire equator C and extending substantially parallel to the outer peripheral surface (tread surface) of the tread ring 6, and the belt width extends over substantially the entire length of the tread width.

Further, as the belt cord, a metal fiber cord such as a steel cord is preferably used in order to protect the carcass 10 to prevent the occurrence of punctures and enhance the safety of traveling.

In this example, the jointless band layer 16 is provided on the outer side in the radial direction of the belt layer 15. The jointless band layer 16 covers at least the outer end of the belt layer 15 in the axial direction of the tire to prevent the outer diameter of the outer end of the belt layer 15 from growing at a high speed.

Therefore, the jointless band layer 16
Is an organic fiber such as aromatic polyamide.
It is formed by spirally winding a cord or two or three cords that are aligned and buried in a topping rubber at a small angle of 5 degrees or less with respect to the tire equator C. In this example, the jointless band layer 16
Is the outer end portion of the tread ring 6 in the tire axial direction (one of the blade surface portions 6S1) and the other outer end portion of the tread ring 6 (the other blade surface portion 6S1) passing radially outside of the belt layer 15.
1), a wide width is formed by spirally winding one cord, and the outer diameter growth of the belt layer 15 is suppressed by more effectively restraining the belt layer 15 over the entire width. This prevents the tread ring 6 and the tire base body 7 from being displaced from each other due to the growth of the outer diameter during high-speed traveling, and extends the extension portion 16A of the jointless band layer 16 arranged at the outer end portion of the tread ring 6. , 16A form lift-preventing reinforcement layers 17 and 17 that prevent the outer end portions from being lifted up by centrifugal force due to tire rotation.

The jointless band layer 16 may be hollowed out so as to cover only the outer end portion of the belt layer 15 in the tire axial direction.

As the lift preventing reinforcement layers 17 and 17, as shown in FIG. 3, a thick cloth-like body using organic fibers, for example, nylon canvas may be used.

However, as shown in FIG. 4, prior to the internal pressure filling of the tire base body 7, and more preferably prior to the rim assembly, the outer peripheral surface 9S of the tread bottom portion 9 of the tire base body 7 is
Place the tread ring 6 and attach it. After that, a standard internal pressure is filled into the inner cavity of the tire base body 7. Tire base 7
Expands outward in the tire radial direction by the filling internal pressure, and at this time, the non-stretchable tread ring 6 having the belt layer 15 and the jointless band layer 16 and the tire base body 7 have a strong pressure contact force and are integrally formed. In addition, it can be surely connected, and can exhibit excellent running performance equivalent to that of a conventional flat radial tire.

On the other hand, since the tread ring 6 and the tire base 7 are integrally connected by the tire expansion due to the internal pressure filling as described above, the tread ring 6 can be removed from the tread bottom 9 by discharging the internal filling pressure. This can be easily performed without using a special tool or the like, and allows the user to replace the tread ring with a new tread ring having no wear or tread ring having another tread pattern for ice and snow roads. As a result, the tire base body 7 can be repeatedly used, and it is possible to inexpensively provide tread patterns having various performances according to the purpose of use and the like while effectively utilizing resources.

(Specific example) Tire size 185 / 70R1 in which the tread ring and the tire base body are formed as independent bodies.
No. 4 tires of this example (Example products 1 and 2) and conventional tires (conventional products) in which the tread ring and the tire base were integrally molded by vulcanization were prototyped based on the specifications in Table 1, and the steering of each tire was performed. The stability performance and the occurrence of slippage between the tread ring and the tire substrate during running were tested.

[0038]

[Table 1]

In the steering stability performance test, the driver's feeling when the vehicle was mounted on an actual vehicle under a standard internal pressure condition and actually run on a dry road surface was evaluated by a 5-point method. In addition, the sliding test was carried out by setting the tire internal pressure to 3.0 ksc.
Change to 1.9ksc, 1.4ksc, and 1.0ksc, and repeat the running cycle of 80km / h (straight ahead) + 20km / h (U-turn). The gap was measured. Also, as a sliding test, the filling internal pressure is 1.9 ks.
The deviation between the tread ring and the tire base body was also measured when a slip angle of 5 degrees was applied under the conditions of c and a load of 400 kgf and the drum was run for 10 minutes. Further, in the lift test of the outer end portion of the tread ring, the lift was measured when the tread ring was run on the drum for 10 minutes under the same conditions as described above.

As shown in Table 1, the tread ring and the tire base are firmly and integrally connected to each other without causing a deviation even under the condition of 53% standard internal pressure, whereby the same steering performance as the conventional one can be exhibited.

[0041]

Since the pneumatic radial tire of the present invention is constructed as described above, the tread ring can be freely attached to and detached from the tire base body, various tread patterns can be provided at low cost, and the tire base body can be repeated. Can be used and resources can be effectively used.

[Brief description of drawings]

FIG. 1 is a meridional sectional view of a tire showing an embodiment of the present invention.

FIG. 2 is an exploded cross-sectional view of a tire showing a tread portion in an enlarged manner.

FIG. 3 is a cross-sectional view showing another aspect of the lift prevention reinforcing layer.

FIG. 4 is a schematic cross-sectional view illustrating a connection between a tread ring and a tire base body.

[Explanation of symbols] 2 bead core 3 bead part 4 Sidewall part 5 tread section 6 tread rings 7 Tire base 9 tread bottom 9S outer peripheral surface 10 carcass 12 Support layer 14 Reinforcement layer 15 Belt layer 16 jointless band layer 16A extension 17 Lift prevention reinforcement layer G tread groove

─────────────────────────────────────────────────── ─── Continuation of the front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) B60C 1/00-19/12

Claims (3)

(57) [Claims] 1. A vulcanized annular tread ring, and a vulcanized tire base body having a tread bottom portion forming a tread portion of a tire by attaching the tread ring to an outer peripheral surface, the tire base body comprising: A carcass having a carcass cord of radial arrangement and folded around the bead core of the bead part from the tread bottom part to the sidewall part, and a rubber composition having a rubber thickness of 0.5 to 5 mm and forming the outer peripheral surface of the tread bottom part. The tread ring includes a belt layer in which belt cords are arranged at an angle of 30 degrees or less with respect to the tire equator, and the outer side in the radial direction of the tire base body by internal pressure filling. Is integrally connected to the tire base body by expansion to the tire axial direction of the tread ring. The end Rutotomoni provided lift preventing reinforcing layer to prevent the floating due to the centrifugal force caused by the tire rotation of the outer end portion, the lift preventing reinforcing layer, said base of said tread ring
One cord or number provided on the outer side
A strip of cords that are aligned and embedded in topping rubber.
Spirally wrap the strip ply at a small angle to the tire equator
Of at least one jointless band layer
A pneumatic radial tire characterized by being a long part . 2. A vulcanized annular tread ring, and
By attaching the tread ring to the outer peripheral surface of the tire
Vulcanized tie with tread bottom forming tread
A tire base body, and the tire base body includes a tread bottom portion to a sidewall portion.
When it is folded back around the bead core of the bead part,
Carcass with carcass cord of radial arrangement
And the rubber that forms the outer peripheral surface of the tread bottom and
Support formed by a rubber composition having a thickness of 0.5 to 5 mm
The tread ring , on the other hand, comprises a belt cord to the tire equator.
And a belt layer arranged at an angle of 30 degrees or less,
Rise also in the radially outer side of the tire body by internal pressure
Is integrally connected to the tire base body by tension, and the outer end portion of the tread ring is attached to the outer end portion in the tire axial direction.
To prevent lifting due to centrifugal force due to tire rotation
The anti- lifting reinforcement layer is provided from the cloth-like body using organic fibers.
A pneumatic radial tire characterized by comprising. 3. The tire base is in a radial direction of the carcass.
On the outside, one or more cords arranged in the tire axial direction
A reinforcing layer made of ply is provided.
The pneumatic radial tire according to 1 or 2 .