JP3399500B2 - Bladder in radial tire molding equipment - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bladder in a radial tire forming apparatus.

[0002]

2. Description of the Related Art Generally, when forming a radial tire, first, ring-shaped bead wires are attached to the bead portions at both ends of a cylindrical carcass, and the bead portions of the carcass can be moved toward and away from each other. Supported by a pair of movable bodies. A bladder made of an elastic material such as rubber is attached between the two moving bodies, and the carcass is arranged on the outer peripheral side of the bladder. Then, compressed air is supplied to the inner side of the bladder to bring the bladder into close contact with the inner peripheral surface of the carcass. By moving the parts toward each other, the carcass is deformed into a toroidal shape. Next, a breaker layer, a tread rubber layer, a sidewall rubber layer, and the like are sequentially attached to the outer surface of the toroidal carcass to complete the molding of the tire before vulcanization.

[0003]

However, in the prior art,
It has been difficult to form a bladder made of an elastic material so that the entire bladder has a uniform expansion rate, or to form the entire bladder to have a uniform thickness. Therefore, when compressed air is supplied to the inner side of the bladder to expand and expand the bladder, the bladder may have a distorted shape instead of the predetermined toroidal shape set in advance. As a result, the carcass that is bulged and deformed via the bladder cannot be molded into a required toroidal shape, and there is a problem that a tire before vulcanization having a good shape cannot be obtained.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a radial tire forming apparatus capable of surely expanding and expanding a predetermined toroidal shape. Providing a bladder.

[0005]

In order to achieve the above object, in the invention of claim 1, the pressure medium is supplied to the inside of the bladder with the cylindrical carcass being arranged on the outer peripheral side of the bladder. In the radial tire molding device that deforms the carcass in a toroidal shape by moving the bead portions at both ends of the carcass in a direction approaching each other while expanding and expanding the axial middle portion of the carcass, the bladder has a core. together the timber and its core material constituting a and the elastic member
The elastic material is composed of an inner layer and an outer layer, and
Sandwiched core between the two layers of the core material, have a high tensile strength
However, an aggregate composed of multiple non-stretchable wire rods, a cloth material to which the wire rods constituting the aggregate are fixed in order to prevent the arrangement disorder of the wire rods, and expansion and contraction to give the cloth material elasticity And that the length and arrangement structure of each wire constituting the aggregate are set so that the aggregate has a predetermined toroidal shape when the bladder is expanded and expanded. Use as a summary.

According to the invention of claim 2, in claim 1,
The aggregate is a lattice-like one composed of a first wire rod arranged along the circumferential direction of the bladder and a second wire rod arranged along a direction intersecting with the first wire rod.

According to a third aspect of the present invention, in the first or second aspect, the cloth material is provided so as to sandwich the aggregate. According to the invention of claim 4, in any one of claims 1 to 3, in a state in which an aggregate is sandwiched between two cloth materials,
The cloth and the cloth are joined to each other by stitching the cloths on both sides of the wire constituting the aggregate with a thread.

According to the invention of claim 5, in claim 4,
The two cloth materials are attached to each other with an adhesive. According to a sixth aspect of the invention, in any one of the first to fifth aspects, the stretch imparting means imparts stretchability to the cloth material in the circumferential direction of the bladder.

According to the invention of claim 7, in claim 6,
The expansion / contraction applying means includes a string-shaped rubber attached to the cloth material along the circumferential direction of the bladder. According to an eighth aspect of the present invention, in any one of the first to seventh aspects, the cloth material is formed by continuously winding a strip having a desired width at a pitch approximate to the width of the strip. Is.

Therefore, the inventions of claims 1 to 8 have the following effects. According to the invention of claim 1, when the pressure medium is supplied to the inner side of the bladder and the bladder is expanded and expanded in diameter, the aggregate in the bladder has a predetermined toroidal shape. Since each wire constituting the aggregate has a high tensile strength, it does not extend with the expanded diameter of the bladder. In addition, the wire material that constitutes the aggregate is fixed to the cloth material, so that the array structure is reliably prevented from being disturbed. As a result, the aggregate is securely retained in the predetermined toroidal shape set in advance. Therefore, the bladder is surely expanded and expanded to have a shape along the shape of the aggregate (in other words, a shape along the shape of the core), that is, a predetermined toroidal shape set in advance.

Further, as the pressure medium is supplied to the inside of the bladder, the cloth material is stretched, and as a result, the bladder is bulged and expanded without difficulty. Then, when the supply of the pressure medium is stopped, the cloth material quickly contracts, and as a result, the bladder is quickly and reliably separated from the carcass deformed in a toroidal shape. In the state where the bladder is not expanded and expanded, the bladder is loosened in its axially intermediate portion, but since the cloth material is stretchable, it is possible to prevent such loosening.

According to the second aspect of the present invention, since there is no risk of the intersection of the first wire and the second wire forming the aggregate being displaced, a predetermined toroidal shape is surely guaranteed when the bladder is expanded and expanded. it can.

According to the third aspect of the invention, by sandwiching the aggregate with the cloth material, both can be easily coupled. According to the invention of claim 4, in a state in which the aggregate is sandwiched between the two cloth materials, both cloth materials are sewn together with a thread using a sewing machine or the like on both sides of the wire material constituting the aggregate. Thereby, the aggregate and the cloth material can be easily and surely coupled.

According to the fifth aspect of the present invention, the aggregate and the cloth material can be bonded more reliably with the adhesive. According to the invention of claim 6, the cloth material is expanded in the circumferential direction with the supply of the pressure medium into the bladder, and as a result, the bladder is bulged and expanded without difficulty. Then, when the supply of the pressure medium is stopped, the cloth material quickly contracts in the circumferential direction, and as a result, the bladder is quickly and reliably separated from the carcass deformed in a toroidal shape. Further, slack in the axially intermediate portion of the bladder can be reliably prevented when the bladder is not expanded and expanded.

According to the seventh aspect of the invention, the elasticity can be easily imparted to the cloth material only by attaching the cord-shaped rubber to the cloth material along the circumferential direction of the bladder. According to the invention of claim 8, two cloth materials are formed by continuously winding a strip having a desired width. Therefore, a cloth material having a uniform width and thickness is provided. Therefore, the bladder is bulged and expanded uniformly as set in advance.

[0016]

DETAILED DESCRIPTION OF THE INVENTION

(First Embodiment) A first embodiment of the present invention will be described below with reference to FIGS.

As shown in FIGS. 4 and 5, the pair of moving bodies 10 are provided with pipe-shaped operating shafts 10a and each operating shaft 10a.
Is connected to a moving mechanism (not shown). Then, with the operation of the moving mechanism, both moving bodies 10 are moved toward and away from each other. The bladder 1 has a substantially cylindrical shape.
The peripheral edge portions of both ends are locked and held by the peripheral edge portions of each moving body 10 via the ring-shaped locking protrusions 1a. A ring-shaped pressing tube 13 is integrally formed on the peripheral edges of both ends of the bladder 1. A supply hole 10b is formed in the operating shaft 10a of one moving body 10, and compressed air as a pressure medium is supplied to the inside of the operating shaft 10a and the supplying hole 10 by a supply device (not shown).
It is supplied to the inside of the bladder 1 via b. As shown in FIG. 4, the carcass 11 having a cylindrical shape is arranged between the moving bodies 10 on the outer peripheral side of the bladder 1, and the bead portions 11 a at both ends of the carcass 11 have ring-shaped bead wires 12 respectively.
Is set.

In this state, the compressed air from the supply device is supplied to the inside of the bladder 1, and both moving bodies 10 are moved by the moving mechanism in the directions approaching each other.
Then, from the state in which the bladder 1 is in close contact with the inner peripheral surface of the cylindrical carcass 11, as shown in FIG. Both bead parts 11a of 11 are moved in the direction approaching each other. As a result, the carcass 11 is bulged and deformed in a toroidal shape.

When the carcass 11 is expanded and expanded in diameter, compressed air is also supplied into each pressing tube 13 to expand the tube 13. Then, as shown in FIG. 5, both ends of the carcass 11 are pressed by the pressing tube 13, and the both ends are bent so as to wrap the bead wire 12. As a result, the bead portions 11a on both ends of the carcass 11
The bead wire 12 is integrally attached to.

After that, a breaker layer, a tread rubber layer, a sidewall layer (all not shown) and the like are sequentially attached to the outer surface of the carcass 11 formed in a toroidal shape as described above. Then, a mold (not shown) having an inner surface shape corresponding to the outer shape of the radial tire before vulcanization is brought into pressure contact with the outer surfaces of these layers, whereby the molding of the radial tire before vulcanization is completed.

A breaker layer, a tread rubber layer, and the like are held in advance on the inner surface of the die, and the die is moved to both moving bodies 10.
The outer peripheral side of the carcass 11 set between them is made to stand by. Then, as the carcass 11 swells and expands in a toroidal shape as described above, the breaker layer, the tread rubber layer, and the like in the mold may be attached to the outer surface of the carcass 11.

As shown in FIGS. 1 to 3, the bladder 1 is
Is composed of a core material 2 and a rubber 3 as an elastic material that covers the core material 2. Incidentally, FIG. 1 is a partially cutaway perspective view showing a state where the bladder 1 is expanded and expanded.
FIG. 3 is a schematic plan view showing the core material 2 in the bladder 1 in an expanded state. The core material 2 is an aggregate 6, a pair of cloth materials 7 and 8 arranged so as to sandwich the aggregate 6, and an expansion / contraction applying means attached to the inner peripheral surface of the inner peripheral cloth material 7. And a plurality of belt-shaped rubbers 9. The rubber 3 is composed of an inner layer 17 arranged on the inner peripheral side of the core material 2 and an outer layer 18 arranged on the outer peripheral side of the core material 2. The core material 2 is sandwiched between both layers 17, 18. Has been. In addition, the locking protrusion 1a and the pressing tube 1
3 is integrally formed with the outer layer 18.

The aggregate 6 is composed of a first yarn 4 and a second yarn 5 as a plurality of wire rods having high tensile strength. The first and second yarns 4 and 5 are formed of aramid fiber such as Kevlar. The first yarn 4 is arranged along the circumferential direction of the bladder 1, the second yarn 5 is arranged along the direction intersecting with the first yarn 4, and the aggregate 6 is the first yarn intersecting with each other. The yarn 4 and the second yarn 5 are formed in a lattice shape.

The first yarns 4 are arranged in parallel with each other along the circumferential direction of the bladder 1. Each first yarn 4
On the bladder 1, it is arranged only in a portion corresponding to the tread portion of the tire to be molded (tread molding portion), and their lengths are substantially the same. The length of each first yarn 4 is the length of the tread forming portion of the bladder 1 when the axially intermediate portion of the bladder 1 (that is, the tread forming portion) is expanded and expanded as shown in FIG. It is set to a length corresponding to the circumference length.

Further, the second yarns 5 are parallel to each other at the tread forming portion of the bladder 1 (that is, the portion corresponding to the disposing portion of the first yarn 4) and the first yarns 4 They are arranged so that they intersect at right angles. And each second yarn 5
At the side wall forming portion of the bladder 1, the axially intermediate portion of the bladder 1 extends in the radial direction around the axial center of the bladder 1 when the bladder 1 is expanded and expanded as shown in FIG. The distance becomes wider from both ends of the adjacent second yarns 5 toward the middle part.

Both ends of each second yarn 5 have the first yarn 4
It is fixed by being tied to the yarn 14 as a wire arranged in parallel with. This yarn 14 is also formed of aramid fiber such as Kevlar, and its length corresponds to the circumferential length of the peripheral edges of both ends of the bladder 1.

As described above, in this embodiment, the aggregate 6 has a predetermined toroidal shape with the axially intermediate portion of the bladder 1 bulging and expanding as shown in FIG. In addition, the length and arrangement structure of each of the yarns 4, 5, and 14 constituting the aggregate 6 are set.

The cloth materials 7 and 8 are arranged so as to sandwich a portion of the aggregate 6 where the first yarn 4 and the second yarn 5 intersect with each other from the inner peripheral surface side and the outer peripheral surface side. ing. Each of the cloth materials 7 and 8 is configured by winding a strip-shaped cloth along the circumferential direction of the aggregate 6, for example. Each of the cloth materials 7 and 8 is wound once or more so that at least both ends thereof overlap each other. Then, in a state in which the aggregate 6 is sandwiched between the cloth materials 7 and 8 in this manner, both cloth materials 7 and 8 are attached to both sides of the first and second yarns 4 and 5 of the aggregate 6 with a sewing machine or the like. By using and stitching with the thread 15, the aggregate 6 and the fabrics 7, 8 are joined together. As a result, the arrangement structure of the first and second yarns 4 and 5 is reliably restrained by the cloth materials 7 and 8 and is not disturbed. As the thread 15 for sewing, it is desirable to use aramid fiber such as Kevlar in terms of strength. Further, when sandwiching the aggregate 6 between the cloth materials 7 and 8, if the cloth materials 7 and 8 are adhered to each other with an adhesive, the aggregate 6 and the cloth materials 7 and 8 are more reliably bonded. Therefore, it is possible to more reliably prevent the disorder of the arrangement structure of the first and second yarns 4 and 5.

The band-shaped rubber 9 is sewn and fixed to the inner peripheral surface of the cloth material 7 on the inner peripheral side by a thread 16 so as to extend in the circumferential direction. The sewing of the thread 16 is also performed using a sewing machine or the like. It is desirable to use aramid fiber such as Kevlar as the thread 16 in terms of strength. The band-shaped rubber 9 imparts elasticity to the cloth materials 7 and 8 in the circumferential direction.

Since the present embodiment has the above-mentioned structure, it has the following operational effects. ○ bladder during one bulge diameter, so as to have a predetermined toroidal shape aggregate 6 is set in advance, the aggregate 6
The length and array structure of each of the yarns 4, 5, and 14 constituting the yarn are set. Therefore, as shown in FIGS. 1 and 5,
When compressed air is supplied to the inside of the bladder 1 and the bladder 1 is expanded and expanded, the aggregate 6 in the bladder 1 has a predetermined toroidal shape. Since each of the yarns 4, 5 and 14 which constitute the aggregate 6 has high tensile strength, the yarn 6 does not grow along with the expanded diameter of the bladder 1 and the aggregate 6 is set to a preset predetermined value. The toroidal shape of is securely retained. Therefore, even if the thickness and the expansion rate of the rubber 3 of the bladder 1 are partially uneven, the bladder 1 has a shape along the shape of the aggregate 6 (in other words, along the shape of the core material 2). Shape), that is, a predetermined toroidal shape that is set in advance, can be swelled and expanded without any difficulty, accurately and reliably. Therefore, the carcass 11 that is bulged and deformed via the bladder 1 can be surely molded into a required toroidal shape, and a tire before vulcanization having a good shape can be obtained.

○ With the aggregate 6 sandwiched between the two cloth materials 7 and 8, the first and second yarns 4 and 4 constituting the aggregate 6
By sewing the cloth materials 7 and 8 on both sides of 5 with the thread 15 using a sewing machine or the like, the aggregate 6 and the cloth materials 7 and 8 can be easily and surely connected. Therefore, the arrangement structure of the yarns 4 and 5 forming the aggregate 6 is not disturbed, and the aggregate 6
Is securely retained in a predetermined toroidal shape set in advance.

Incidentally, the first yarn 4 and the second yarn 4 which intersect each other
It is also conceivable to connect the yarn 5 to each of the intersections by thermocompression bonding, an adhesive or the like, or by a method such as tying with a thread. However, it is impossible to bond Kevlar which is the most suitable material for the yarns 4 and 5 by thermocompression bonding, and it is difficult to penetrate the adhesive into the Kevlar. The binding force of is insufficient. Further, the work of connecting the intersections of the yarns 4 and 5 with the yarn is very troublesome and troublesome. However, as in this embodiment, the aggregate 6
When the two are sewn with a sewing machine or the like while being sandwiched between the two cloth materials 7 and 8, the connection can be easily performed, and
Sufficient bond strength can be obtained.

The band-shaped rubber 9 gives the cloth materials 7, 8 elasticity in the circumferential direction. Therefore, as the compressed air is supplied into the bladder 1, the cloth materials 7 and 8 expand in the circumferential direction, and as a result, the bladder 1 expands and expands in diameter without difficulty. When the supply of compressed air is stopped, the cloth material 7,
8 rapidly contracts in the circumferential direction, so that the bladder 1 is quickly and reliably separated from the toroidally deformed carcass 11. Further, in the state where the bladder 1 is not expanded and expanded, the slack is generated at the intermediate portion in the axial direction.
Since it can be expanded and contracted in the circumferential direction, it is possible to reliably prevent such looseness. Further, the elastic properties can be easily imparted to the cloth materials 7 and 8 only by sewing the band-shaped rubber 9 to the cloth materials 7 and 8 along the circumferential direction of the bladder 1.

(Second Embodiment) Next, a second embodiment of the present invention will be described with reference to FIG. In the second embodiment, the same members as those in the first embodiment are designated by the same reference numerals, and the description thereof will be simplified.

FIG. 6 is a partially enlarged perspective view showing the core material 2 of the bladder 1 according to the second embodiment. As shown in the same figure, in this 2nd Embodiment, the 1st thread 4 in the said 1st Embodiment is not provided, but each cloth material 7,8 has 2 layer structure instead, A plurality of yarns 19 as wires having high tensile strength are sandwiched between the layers of the cloth materials 7 and 8. This yarn 19 is also made of aramid fiber such as Kevlar, like the first yarn 4,
They are arranged parallel to each other along the circumferential direction of the bladder 1. In each of the cloth materials 7 and 8, the first layer and the second layer are attached to each other with an adhesive, for example. If the first layer and the second layer of the cloth materials 7 and 8 are sewn on both sides of the yarn 19, the disorder of the arrangement of the yarns 19 can be more surely prevented.

Also in the second embodiment having such a configuration, the same operational effect as that of the first embodiment can be obtained. The second embodiment can be embodied by changing the configuration of each unit as follows.

(Modification) In the above second embodiment,
Instead of the two-layer structure cloth materials 7 and 8 including the yarn 19, use cloth materials 7 and 8 as shown in FIG. 7. In the cloth materials 7 and 8 shown in FIG. 7, a plurality of yarns 20 as wires having high tensile strength are sewn at predetermined intervals as warp threads constituting the cloth materials 7 and 8. . This thread 20
Like the yarn 19 in the second embodiment, the yarn is formed of aramid fiber such as Kevlar and is arranged along the circumferential direction of the bladder 1. In this way, if the yarn 20 is provided as a part of the warp of the cloth materials 7 and 8, the yarn 20 can be reliably fixed to the cloth materials 7 and 8, and the arrangement disorder can be surely prevented. .

Therefore, even with this configuration, the first
Also, the same effect as that of the second embodiment can be obtained. The first and second embodiments can be modified and embodied as follows.

(Modification) In each of the above-described embodiments, the width of the cloth materials 7 and 8 is formed so that the cloth materials 7 and 8 can cover almost the entire aggregate 6. (Modification) The pressing tube 13 is provided separately from the bladder 1.

(Third Embodiment) Next, a third embodiment of the present invention will be described with reference to FIGS.
In the third embodiment, the same members as those in the first and second embodiments will be designated by the same reference numerals, and the description will be focused on the portions different from the above-described embodiments.

As shown in FIGS. 8 and 9, the strip 21 is
It has a desired width W and is continuously wound in the tire circumferential direction at a pitch similar to the width W of the strip 21. That is, when the strip 21 having a desired width W is wound around once and 8A turns are completed, 8B turns are wound while the side end portions of the strip 21 are brought into contact with each other. Similarly, 8C turn, 8D turn, ... 8
The cloth material 8 is provided by continuously winding the Z-turn and the strip 21. Further, the cloth material 7 is also configured similarly to the cloth material 8 and is provided by continuously winding the strip 21.

Next, a method of molding a tire using the bladder 1 will be described. As shown in FIG. 10, the pair of moving bodies 22 includes pipe-shaped actuating shafts 22a, and each actuating shaft 22a is connected to a moving mechanism (not shown). The two moving bodies 22 are set to approach or separate from each other in accordance with the operation of the moving mechanism. Further, the moving body 22 has a jig 23 whose diameter can be expanded / contracted, and this jig 23 is associated with the operation of the moving mechanism.
It is configured to project in the radial direction.

The bladder 1 has a substantially cylindrical shape, and both peripheral edges of the bladder 1 are retained by the peripheral edge of the moving body 22. That is, ring-shaped locking projections 24a, 25a extending in the circumferential direction are provided on the inner peripheral edges of both ends of the inner layer 24 and the outer layer 25 that constitute the elastic material sandwiching the core material 2. The strips 24a and 25a are locked and held by locking portions 26 and 27 provided on the peripheral edge of the moving body 22. Further, both ends of the second yarn 5 constituting the core material 2 are fixed by being tied to a yarn 14 as a wire arranged in parallel with the first yarn 4 (see FIG. 8). , This thread 14 is a moving body 22
It is locked and held by the locking portion 28 of the. The carcass 11 having a substantially cylindrical shape has two moving bodies 22 on the outer peripheral side of the bladder 1.
Ring-shaped bead wires 29 are set outside the both ends of the carcass 11.

Thus, the carcass 1 in which the bladder 1 has a cylindrical shape
1, compressed air is supplied to the inside of the bladder 1 in a state of being in close contact with the inner peripheral surface of the moving body 22,
Are moved toward each other. Then, as shown in FIG. 11, the bead portions of the carcass 11 move toward each other while the axially intermediate portion of the carcass 11 bulges and expands through the bladder 1. As a result, the carcass 11 is bulged and deformed in a toroidal shape. Subsequently, the jig 23 is expanded in diameter. Then, since both ends of the carcass 11 are pressed and inverted, the bead wires 29 are included in the bead portions at both ends of the carcass 11 and are integrally attached.

According to the bladder in the radial tire molding apparatus of the third embodiment having the above-described structure, the cloth materials 7 and 8 are provided by continuously winding the strip 21.
Therefore, it is possible to obtain the same effect as each of the above-described embodiments, and there is no overlapping portion of the end portions of the cloth materials 7 and 8 at a specific position in the circumferential direction, and further, the cloth materials 7 and 8 become the sidewall portions. Since the bladder 1 is also arranged, it is possible to realize a uniform bulge expansion of the bladder 1 as set.

The third embodiment can be modified and embodied as follows. That is, the number of winding layers of the band 21 may be increased only in the axially intermediate portion of the carcass 11. Even with this configuration, the same effect as that of the third embodiment can be obtained, and the intermediate portion, which is likely to have a round shape, can maintain the flat shape as much as possible.

The first to third embodiments can be modified and embodied as follows. (Modification) Instead of arranging the second thread 5 between the cloth materials 7 and 8, the cloth material is sewn with the second thread 5 so that the second thread 5 is woven. You may provide so that it may expose to the outer peripheral side and the inner peripheral side by turns. Even if formed in this way, the same effects as those of the above-described respective embodiments can be obtained.

(Modification) Threads 4, 5, 14, 19, 2
0 was made of Kevlar, but other materials,
For example, it may be formed of an organic fiber other than Kevlar or a metal material.

(Modification) Threads 4, 5, 14, 19, 2
The number of 0s may be appropriately changed according to the size and type of the tire to be molded. (Modification) The first yarn 4 may be a strip-shaped wire having a certain width.

[0050]

As described in detail above, the present invention has the following excellent effects. According to the invention of claim 1, when the pressure medium is supplied to the inside of the bladder, the bladder can be surely expanded and expanded in a predetermined toroidal shape set in advance. Therefore, the carcass that is bulged and deformed via the bladder can be surely molded into a required toroidal shape, and a tire before vulcanization having a good shape can be obtained. Moreover, the bladder can be expanded and expanded without difficulty, and the bladder can be quickly and surely peeled off from the carcass formed in the toroidal shape. In addition, it is possible to reliably prevent looseness in the axially intermediate portion of the bladder when the bladder is not expanded and expanded.

According to the second aspect of the present invention, since there is no risk of the intersection of the first wire and the second wire constituting the aggregate being displaced, a certain toroidal shape is surely guaranteed when the bladder is expanded and expanded. it can.

According to the third aspect of the present invention, by sandwiching the aggregate with the cloth material, the both can be easily combined. According to the invention of claim 4, the aggregate and the cloth material can be easily and surely coupled.

According to the fifth aspect of the present invention, the aggregate and the cloth material can be more surely bonded with the adhesive. According to the invention of claim 6, the bladder can be bulged and expanded in diameter without difficulty, and the bladder can be quickly and reliably peeled off from the carcass formed in the toroidal shape.
In addition, it is possible to reliably prevent looseness in the axially intermediate portion of the bladder when the bladder is not expanded and expanded.

According to the seventh aspect of the invention, the elasticity can be easily imparted to the cloth material only by attaching the cord-shaped rubber to the cloth material along the circumferential direction of the bladder. According to the invention of claim 8, since there is no overlapping portion of the end portions of the cloth material at a specific position in the circumferential direction, it is possible to realize a uniform expanded diameter of the bladder as set.

[Brief description of drawings]

FIG. 1 is a partially cutaway perspective view showing a first embodiment of a bladder in a radial tire forming apparatus embodying the present invention.

FIG. 2 is a perspective view of an essential part showing an enlarged part of a core material.

FIG. 3 is a schematic plan view showing the core material in a developed state.

FIG. 4 is a cross-sectional view showing a state in which a carcass is set in a molding device.

FIG. 5 is a cross-sectional view showing a state in which a carcass is bulged and expanded by a molding device.

FIG. 6 is a partially enlarged perspective view showing a core material according to a second embodiment.

FIG. 7 is a partial plan view schematically showing a part of a cloth material in a modified example.

FIG. 8 is a partially cutaway perspective view showing a third embodiment of a bladder in a radial tire forming apparatus embodying the present invention.

FIG. 9 is a perspective view of an essential part showing an enlarged part of a core material according to a third embodiment.

FIG. 10 is a cross-sectional view showing a state in which the carcass is set in the molding device.

FIG. 11 is a cross-sectional view showing a state where the carcass is expanded and expanded in diameter by a molding device.

[Explanation of symbols]

1 ... Bladder, 2 ... Core material, 3 ... Rubber as elastic material, 4 ...
First yarn as wire rod, 5 ... Second yarn as wire rod, 6
... aggregate, 7 ... cloth material, 8 ... cloth material, 9 ... band-shaped rubber as expansion / contraction applying means, 10 ... moving body, 11 ... carcass, 14 ... yarn as wire material, 15 ... thread, 16 ... thread, 17 ... inner layer,
18 ... Outer layer, 19 ... Yarn as wire, 20 ... Yarn as wire, 21 ... Band.

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Claims (8)

(57) [Claims] 1. A cylindrical carcass is arranged on the outer peripheral side of the bladder to supply a pressure medium to the inside of the bladder so as to swell and expand the axially intermediate portion of the carcass, and the bead portions at both ends of the carcass. by moving the towards each other, to configure the molding device of the radial tire to deform the carcass toroidally, the bladder, the core and its core by the elastic member
In addition, the elastic material is composed of an inner layer and an outer layer.
The core material is sandwiched between the two layers, and the core material has a high tensile strength and prevents the aggregates composed of a plurality of non-stretchable wire rods and the arrangement disorder of the wire rods forming the aggregated material. For this purpose, it has a cloth material to which the same wire is fixed, and an expansion / contraction applying means for giving elasticity to the cloth material, and when the bladder is expanded and expanded, the aggregate becomes a predetermined toroidal shape. As described above, the bladder in the radial tire forming apparatus in which the length and arrangement structure of each wire constituting the aggregate are set. 2. The grid-shaped aggregate is composed of a first wire rod arranged along a circumferential direction of the bladder and a second wire rod arranged along a direction intersecting with the first wire rod. The bladder in the apparatus for molding a radial tire according to claim 1, which is one. 3. The bladder in the radial tire forming apparatus according to claim 1, wherein the cloth material is provided so as to sandwich the aggregate. 4. A state in which an aggregate is sandwiched between two cloth materials,
The bladder in the radial tire molding apparatus according to any one of claims 1 to 3, wherein the aggregate and the cloth material are connected to each other by sewing both cloth materials on both sides of the wire material that constitutes the aggregate with a thread. . 5. The bladder for a radial tire forming apparatus according to claim 4, wherein the two cloth materials are attached to each other with an adhesive. 6. The bladder in a radial tire molding apparatus according to claim 1, wherein the stretch imparting means imparts stretchability to the cloth material in a circumferential direction of the bladder. 7. The expansion / contraction applying means includes a cord-shaped rubber attached to a cloth material along the circumferential direction of the bladder.
The bladder in the radial tire forming apparatus according to claim 1. 8. The radial member according to claim 1, wherein the cloth material is formed by continuously winding a strip having a desired width at a pitch close to the width of the strip. Bladder in tire forming equipment.