JPH11320697A - Manufacture of tire containing sealer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To form a sealer chamber of an accurate shape by clarifying a boundary between a vulcanized adhesive part and non-vulcanized part in the case of vulcanizing to mold a crude tire. SOLUTION: The method for manufacturing a tire containing sealer comprises the steps of setting a crude tire 24 obtained by superposing a tire body 1 and an inner liner 2 in an upper mold 29 and a lower mold 30, expanding a bladder 31 from its inside with an air pressure, and vulcanizing to mold it. At this time, a mold release sheet 9 such as a fluororesin sheet or the like having mold releasability only on one side surface is interposed between the liner 2 and the body 1 with the surface having the mold releasability opposed to the liner 2 to prevent the liner 2 from being vulcanized to be adhered to the body 1, and hence sealer chamber for filling a sealer can be formed in an accurate shape. When the sheet 9 is constituted by a material for dissolving in the sealer, a decrease in the sealability of the sheet 9 remained in the chamber can be avoided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a tire containing a sealant having a ring-shaped sealant chamber partitioned by an inner liner inside a tread.

[0002]

2. Description of the Related Art Inside a tread of a tire body, a sealing agent chamber at least partly partitioned by an inner liner is formed, and a puncture of the tread by a nail or the like is self-sealed with a sealing agent sealed in the sealing agent chamber. Japanese Patent Application Laid-Open No. Hei 8 (1994) discloses a tire containing a sealant that delays air leakage from a puncture.
It is known from JP-A-323875.

[0003] In the conventional tire containing a sealant, when the inner liner is superimposed on the tire body before vulcanization molding, talc or the like is formed on a part of a contact surface between the two or a part of a contact surface between the inner liners. By performing vulcanization molding in a state where the release agent is applied, the inner liner is integrated with the tire main body, and a portion where the release agent is applied is left in a non-adhered state to form a sealant chamber. It has become.

[0004]

When a green tire comprising a tire body and an inner liner is inserted into a heating mold and vulcanized to form the inner liner, the inner liner is stretched. A low portion may occur, and the boundary between the portion to be vulcanized and bonded and the portion not to be vulcanized may be unclear, so that a completely shaped sealant chamber may not be formed. Therefore, it is difficult to form a sealant chamber having a desired shape, and there is a problem that the degree of freedom in designing the shape of the sealant chamber is limited.

The present invention has been made in view of the above-mentioned circumstances, and when vulcanizing and molding a green tire, a boundary between a portion to be vulcanized and bonded and a portion not to be vulcanized is made clear to form a sealant chamber having an accurate shape. It is intended to be able to form.

[0006]

Means for Solving the Problems To achieve the above object, the invention described in claim 1 is characterized in that an inner liner is superposed on the inner surface of a tire body before vulcanization molding and vulcanization molding is performed. At least a part of the inner liner is vulcanized and adhered to the inner surface of the tire main body, and in a method of manufacturing a tire containing a sealant forming a ring-shaped sealant chamber partitioned by the inner liner inside a tread, before vulcanization molding, A release sheet having releasability is disposed at a portion of the inner liner facing the sealant chamber.

According to the above configuration, when the inner liner is overlaid on the inner surface of the tire main body before vulcanization molding, the release sheet having releasability is arranged at a portion facing the sealant chamber of the inner liner. In the vulcanization molding, the portion of the inner liner facing the sealant chamber can be reliably prevented from being vulcanized and bonded, and the portion not facing the sealant chamber can be reliably vulcanized and bonded. Accordingly, the degree of freedom in designing the shape of the sealant chamber is improved, and the sealant chamber can be formed in an accurate shape.

According to a second aspect of the present invention, in addition to the configuration of the first aspect, at least a part of one surface of the release sheet has a release property, and the release sheet is released. The part having no property is vulcanized and adhered to the wall surface of the sealant chamber during vulcanization molding.

According to the above configuration, since the release sheet has the part having the releasing property and the part having no releasing property, the vulcanization adhesion of the inner liner is prevented at the part having the releasing property. Thus, the sealant chamber can be formed, and the inner liner can be vulcanized and adhered to the wall surface of the sealant chamber at a portion having no releasability to prevent the inner liner from being perturbed. In addition, if the part having releasability is a part of one surface of the release sheet, the inner liner is connected to the inner surface of the tire body at that part, and the shape of the sealant chamber can be stabilized.

According to a third aspect of the present invention, in addition to the configuration of the first aspect, the release sheet is made of a material dissolvable in the sealant, and is dissolved by injecting the sealant into the sealant chamber. It is characterized by doing.

According to the above configuration, when the sealant is injected into the sealant chamber, the release sheet dissolves in the sealant, so that it is possible to reliably prevent a decrease in sealing performance due to the residual release sheet.

According to a fourth aspect of the present invention, in addition to the configuration of the third aspect, the release sheet is made of water-soluble paper or nonwoven fabric.

According to the above configuration, the release sheet can be reliably dissolved by injecting the sealant.

According to a fifth aspect of the present invention, in addition to the configuration of the first aspect, a plurality of release sheets are stacked and arranged.

According to the above construction, even when the release sheet is stretched together with the tire body and the inner liner during vulcanization molding, the plurality of release sheets slide on each other at the contact surfaces thereof, and the release sheet is broken. As a result, undesirable vulcanization adhesion between the tire body and the inner liner can be reliably avoided.

According to a sixth aspect of the present invention, in addition to the configuration of the first aspect, the release sheet is folded into a corrugated shape before vulcanization molding, and the release sheet is stretched during vulcanization molding. It is characterized by the following.

According to the above construction, even if the release sheet is stretched together with the tire body and the inner liner at the time of vulcanization molding, the release sheet folded in a corrugated manner is freely stretched to prevent breakage. And undesired vulcanization adhesion of the inner liner can be reliably avoided.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described based on embodiments of the present invention shown in the accompanying drawings.

1 to 5 show a first embodiment of the present invention. FIG. 1 is a cross-sectional view of a wheel on which a tire is mounted, FIG. 2 is a first partial view of a tire manufacturing process, and FIG. FIG. 4 is an enlarged sectional view taken along line 4-4 of FIG. 2, and FIG. 5 is an enlarged sectional view taken along line 5-5 of FIG.

As shown in FIG. 1, a tubeless tire T comprising a tire main body 1 and an inner liner 2 vulcanized and bonded therein is mounted on a rim R of a motorcycle wheel. The left and right sides of the inner liner 2 except for the central portion are vulcanized and bonded to the inner surface of the tire body 1, and an air chamber 5 having a substantially circular cross section is defined inside the inner liner 2. A sealant chamber 6 having a substantially arc-shaped cross section is defined between the inner surface of the main body 1 and the sealant chamber 6. Sealant room 6
Is filled with a known liquid sealant 7.

The rim R has an annular rim main body 11 extending in the circumferential direction of the tire T, and a pair of flanges extending radially outward from both ends in the width direction of the rim main body 11 to hold the inner periphery of the tire main body 1. 12, 12 are provided. An air valve 13 that fills the air chamber 5 formed inside the inner liner 2 with air is supported through an air valve attachment portion 14 formed at one location in the circumferential direction of the rim main body 11.

Since the sealant chamber 6 of the inner liner 2 is held in a shape along the inside of the tread 15 by the air pressure of the air chamber 5, the tire body 1 is punctured from the radial direction or from the side by a nail or the like. However, the sealant 7 immediately fills and repairs the puncture, and delays the leakage of air from the air chamber 5. Further, since the sealant 7 is held in the sealant chamber 6 and does not flow out to the air chamber 5 side,
There is no clogging of the air valve 13 or the pressure gauge applied thereto.

Next, a manufacturing process of the tire T will be described with reference to FIGS.

The manufacturing process of the tire T includes an inner liner winding process, a release sheet winding process, a green tire winding process, a mold setting process, a vulcanization process, a sealant injection process, and an inspection process.

First, a tubular inner liner 2 made of raw rubber is fitted around the drum 23 in an inner liner winding step, and a release sheet 9 is wound around the inner liner 2 in a subsequent release sheet winding step. . Then, in a raw tire winding step, the raw material of each part of the tire main body 1 is wound around the outer periphery of the inner liner 2 and the release sheet 9 to form a raw tire 24.

[0026] Figure 4 shows a cross section of the green tire 24 wrapped around the drum 23, and most of the width W ₁ of the inner liner 2 situated inside, the release sheet was superimposed on the outer side 9 the width W ₂ of is smaller, thus a part of the inner liner 2 from left and right ends of the release sheet 9 projects. The release sheet 9 is made of a fluororesin sheet (Teflon sheet) or a silicon resin sheet having a thickness of 50 μm or less, and a commercially available product is available. For example,
As a Teflon sheet, there is Aflex (trade name) of Asahi Glass Co., Ltd.

The release sheet 9 has one surface subjected to a corona discharge treatment or a CS treatment, and the surface subjected to the treatment loses the releasability and the adhesion to rubber is enhanced. I have. Then, one surface on which the above-described processing is performed is the tire body 1
, And the other untreated surface having release properties contacts the inner liner 2.

In the corona discharge treatment, the surface is made of polyester,
A high-pressure corona discharge is generated between an electrode connected to a high-voltage generator and the metal roll while running the release sheet 9 as an object to be processed along a metal roll covered with a Hypalon, EP rubber, or the like. The ozone or nitric oxide that has generated corona reacts with the surface of the release sheet 9 to generate carbonyl groups and the like, so that the surface becomes hydrophilic. In the CS process, a plasma discharge process is performed under vacuum instead of the corona discharge, and the same operation and effect as the corona discharge process can be obtained.

The tire body 1 made of raw rubber is wound around the outer periphery of the inner liner 2 and the release sheet 9 to form a raw tire 24. The tire main body 1 includes a cord portion 25 wound around the inner liner 2 and the release sheet 9 in the radial direction, and a pair of beads fitted to the outer periphery of the inner liner 2 so as to be connected to both axial ends of the cord portion 25. And a tread portion 27 wound around the cord portion 25 and the bead portions 26, 26 so as to cover the outside in the radial direction.

Subsequently, the raw tire 24 removed from the drum 23 is set between the upper mold 29 and the lower mold 30 for vulcanization molding in a mold setting step. Further, the upper mold 29 and the lower mold 30 are heated in the vulcanization step shown in FIG.
4 is inflated by air pressure, and the raw tire 24 is pressed by the upper mold 29 and the lower mold 30 with the pressure.
And vulcanization molding so as to obtain a final product shape. In this vulcanization molding, the inner liner 2 is integrated with the tire main body 1.

At this time, the release sheet 9 is sandwiched and compressed between the inner liner 2 and the tire main body 1 by the pressure of the expanding brother 31, and the other side of the release sheet 9 contacting the inner liner 2 of the release sheet 9 is compressed. The surface (that is, the surface that has not been subjected to the surface treatment) is not vulcanized and bonded to the inner liner 2, and one surface that contacts the tire body 1 (that is,
The surface-treated side) is vulcanized and bonded to the tire body 1.

By using the release sheet 9 in this manner, the parts that need to be vulcanized are securely vulcanized and bonded, and the parts that should not be vulcanized are securely left unbonded. The sealant chamber 6 having a correct shape can be formed between the inner liner 2 and the tire main body 1. Further, since the release sheet 9 is fixed to the inner surface of the tire main body 1 by being vulcanized and adhered, the release sheet 9 may be perturbed inside the sealant chamber 6 and obstruct the free flow of the sealant 7. In addition, the sealing effect by the sealing agent is reliably exhibited.

After the vulcanization molding has been completed, the integrated tire body 1 and inner liner 2 are taken out of the mold, and the sealant 7 is inserted into the sealant chamber 6 using a syringe or the like in a sealant injection step. To complete the tire T,
In the final inspection step, the finished product is inspected and all the steps are completed.

Next, a second embodiment of the present invention will be described with reference to FIGS.

As shown in FIG. 6, the tire T of the second embodiment
Includes a first inner liner 2 ₁ is vulcanization bonded to the radially outer portion of the inner surface of the tire body 1, pressure in the left and right ends of the radially inner portion and the first inner liner 2 ₁ of the inner surface of the tire body 1 vulcanization is wearing, and a second inner liner 2 ₂ defining a sealant chamber 6 between the first inner liner 2 _1. Release sheet 9 to the first inner liner 2 ₁ wall facing the sealant chamber 6 is fixed by vulcanization bonding.

[0036] Figure 7 shows a green tire wrapping step for the tire T of the second embodiment, the release sheet 9 is wound around the second outer circumference of the inner liner 2 ₂ which is wound around the outer circumference of the drum 23, further Outside the first inner liner 2
₁ is wound. Release sheet 9, the surface facing the first inner liner 2 ₁ is corona discharge treatment or CS
Handle decorated with bonded by vulcanization to the first inner liner 2 ₁ and the surface facing the second inner liner 2 ₂ forms a sealant chamber 6 exerts a releasing property. According to the second embodiment, the same operation and effect as those of the first embodiment can be obtained.

Next, a third embodiment of the present invention will be described with reference to FIGS.

As shown in FIG. 8, the tire T of the third embodiment
Has a single inner liner 2 like the tire T of the first embodiment, and both ends of the inner liner 2 are vulcanized and bonded to the inner surface of the tire body 1 as in the first embodiment. Not only that, the central part has a predetermined width (for example, 5
mm) on the inner surface of the tire body 1. Therefore, the sealant chambers 6, 6 are separated into two chambers on the left and right sides of the center of the inner liner 2 at the bonding portion 32, stabilizing the shape of the sealant chambers 6, 6 and increasing the size of the tire T. In this case, the movement of the sealant 7 in the sealant chambers 6, 6 can be minimized.

FIG. 9 shows a raw tire winding process of the tire T according to the third embodiment, in which two release sheets 9, 9 are provided on the outer periphery of the inner liner 2 wound around the outer periphery of the drum 23.
9 are wound around each other at an interval of 5 mm, and further, the raw material of each part of the tire main body 1 is wound around the periphery thereof to form a raw tire 24. The surfaces of the release sheets 9 and 9 facing the inner liner 2 have releasability, and the surfaces facing the tire main body 1 are removed from the releasability by corona discharge treatment or CS treatment. Thereby, the sealing agent chambers 6 and 6 divided into two chambers can be formed in an accurate shape.

When the tire T having the structure shown in FIG. 8 is manufactured, the two release sheets 9, 9 are arranged at intervals in the third embodiment, but the following two methods are used. Ba 1
The same effect can be obtained by using a single release sheet 9.

In the first method, the entire surface of the release sheet 9 facing the tire main body 1 is eliminated by corona discharge treatment or CS treatment, and a part of the surface facing the inner liner 2 is further removed. The mold release property is eliminated by corona discharge treatment or CS treatment. By doing so, a part of the surface on the opposite side of the release sheet 9 adhered to the tire main body 1 is adhered to the inner liner 2, so that the tire T having the structure shown in FIG. 8 can be obtained. The portion of the surface facing the inner liner 2 that eliminates the releasability may be linear or spot-shaped.

In the second method, a slit-shaped opening or a spot-shaped opening is previously formed in the release sheet 9 in which the surface facing the tire body 1 has been released from the release property by corona discharge treatment or CS treatment. Things. By doing so, the inner liner 2 comes into contact with the tire body 1 via the opening of the release sheet 9 and is vulcanized and bonded, so that the tire T having the structure shown in FIG. 8 can be obtained.

Next, a fourth embodiment of the present invention will be described with reference to FIGS.

In each of the first to third embodiments, one release sheet 9 is used, but as shown in FIG.
In an embodiment the release sheet 9 ₁ of three in the first inner liner 2 ₁ and the second between the inner liner 2 ₂ in the state of the raw tire 24, 9 _2, 9 ₃ are arranged in a stacked state. The three release sheets 9 ₁ , 9 ₂ , 9 ₃ are made of a material that dissolves in the sealant 7 containing water and ethylene glycol as main components, for example, water-soluble paper or nonwoven fabric.

As described above, the three release sheets 9₁, 9_Two,
9_ThreeBy laminating the raw tire 24 in the vulcanization process.
Set between the upper mold 29 and the lower mold 30 and heat
When vulcanizing to the final product shape, release sheet
9₁, 9_Two, 9_ThreeOf the first inner liner
ー 2₁And the second inner liner 2_TwoAre vulcanized with each other
It can be reliably prevented from being worn. Because
For example, at the time of the vulcanization molding, the release sheet 9 together with the green tire 24 is used.
₁, 9_Two, 9_ThreeIs drawn in the direction of arrow aa in FIG.
The three release sheets 9 are stretched.₁, 9_Two,
9_ThreeAre skewed to each other to prevent breakage.
The first inner liner 2₁And the second inner
Liner 2_TwoWill no longer be in direct contact
You. At this time, the central release sheet 9_TwoTalc on both sides
If put on, release sheet 9₁, 9 _Two, 9_ThreeMutual sliding
Better to prevent breakage.
You.

The sealant 7 is provided inside the sealant chamber 6.
As shown in FIG. 11B, the release sheets 9 ₁ , 9 ₂ , 9 ₃ remaining in the sealant chamber 6 are dissolved, so that the release sheets 9 ₁ , 9 ₂ , 9 ₃ remain. More sealing agent 7
It is possible to reliably prevent the sealing property from being hindered.

Next, a fifth embodiment of the present invention will be described with reference to FIG.

The fifth embodiment is a modification of the fourth embodiment.
Release sheets 9₁, 9_Two, 9_ThreeOne of them, for example
Central release sheet 9_TwoIs formed into a waveform in advance.
You. In this way, the raw tire 24 is finally finished in the vulcanization process.
When vulcanizing to a product shape, the raw tire 24
With 3 release sheets 9₁, 9_Two, 9_ThreeIs stretched
If the two release sheets 9 are₁, 9_ThreeBreaks
The corrugated release sheet 9_TwoIs extended linearly
Since breakage is prevented, the first inner liner 2 ₁And
And second inner liner 2_TwoVulcanize each other in direct contact
Adhesion can be reliably prevented.

Although the embodiments of the present invention have been described in detail, various design changes can be made without departing from the gist of the present invention.

For example, the first to third embodiments and the fifth embodiment
Release sheets 9, 9 in the example₁, 9_Two, 9 _ThreeDissolved in sealant 7
It can be made of a material to be understood. 4th and 5th real
In the embodiment, the release sheet 9₁, 9_Two, 9_ThreeThree layers
However, two or four or more sheets can be laminated.
You.

[0051]

As described above, according to the first aspect of the present invention, when the inner liner is overlaid on the inner surface of the tire main body before vulcanization molding, the inner liner is separated from the portion facing the sealant chamber. Since the release sheet having moldability is arranged, the vulcanization molding reliably prevents the portion facing the sealant chamber of the inner liner from being vulcanized and bonded,
A portion that does not reach the sealing agent chamber can be securely vulcanized and bonded. Accordingly, the degree of freedom in designing the shape of the sealant chamber is improved, and the sealant chamber can be formed in an accurate shape.

According to the second aspect of the present invention,
Since the release sheet has a part having a releasing property and a part having no releasing property, it is necessary to form a sealant chamber by preventing vulcanization adhesion of the inner liner at the part having the releasing property. The inner liner is vulcanized and adhered to the wall surface of the sealant chamber at a portion having no releasability, thereby preventing the inner liner from being perturbed. In addition, if the part having releasability is a part of one surface of the release sheet, the inner liner is connected to the inner surface of the tire body at that part, and the shape of the sealant chamber can be stabilized.

According to the third aspect of the present invention,
When the sealant is injected into the sealant chamber, the release sheet dissolves in the sealant, so that it is possible to reliably prevent a decrease in sealing performance due to the residual release sheet.

According to the fourth aspect of the present invention,
The release sheet can be reliably dissolved by injecting the sealant.

According to the fifth aspect of the present invention,
Even if the release sheet is stretched together with the tire body and the inner liner during vulcanization molding, a plurality of release sheets slide on each other at their contact surfaces to prevent breakage of the release sheet. Undesirable vulcanization of the liner can be reliably avoided.

According to the invention described in claim 6,
Even if the release sheet is stretched together with the tire body and the inner liner during vulcanization molding, the release sheet folded in a corrugated shape is freely stretched to prevent breakage, so that undesired vulcanization adhesion between the tire body and the inner liner is prevented. Can be reliably avoided.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a wheel equipped with a tire.

FIG. 2 is a first partial view of a tire manufacturing process diagram.

FIG. 3 is a second partial view of a tire manufacturing process diagram.

FIG. 4 is an enlarged sectional view taken along line 4-4 of FIG. 2;

FIG. 5 is an enlarged sectional view taken along line 5-5 of FIG. 3;

FIG. 6 is a cross-sectional view of a wheel equipped with a tire according to a second embodiment.

FIG. 7 is a view according to a second embodiment and corresponding to FIG. 4;

FIG. 8 is a cross-sectional view of a wheel on which a tire according to a third embodiment is mounted.

FIG. 9 is a view corresponding to FIG. 4 according to a third embodiment.

FIG. 10 is a view according to a fourth embodiment, corresponding to FIG. 4;

FIG. 11 is a view showing a state at the time of completion of a vulcanization step and at the time of completion of a sealant injection step according to a fourth embodiment.

FIG. 12 is a view corresponding to FIG. 4 according to a fifth embodiment;

[Explanation of symbols]

REFERENCE SIGNS LIST 1 tire main body 2 inner liner 2 ₁ first inner liner (inner liner) 2 ₂ second inner liner (inner liner) 6 sealant chamber 7 sealant 9 release sheet 9 ₁ release sheet 9 ₂ release sheet 9 ₃ release Mold sheet 15 tread

Claims (6)

[Claims] 1. A innerliner to the inner surface of the vulcanization before the tire body (1) (2, 2 _1, 2 ₂₎ the inner liner (2, 2 ₁ by vulcanization molding by superimposing,
At least a portion of 22 ₂ ) is vulcanized and bonded to the inner surface of the tire body ₁ , and a ring-shaped sealant chamber (2, 2 ₁ , 2 ₂ ) partitioned inside the tread 15 by the inner liner 2. 6) A method of manufacturing a tire containing a sealant, the mold release sheet having a releasable property at a portion of the inner liner (2, 2 ₁ , 2 ₂ ) facing the sealant chamber (6) before vulcanization molding. (9, 9 ₁ , 9 ₂ , 9 ₃ ). A method for producing a tire containing a sealant, comprising: 2. At least a part of one surface of the release sheet (9) has releasability, and a part of the release sheet (9) that does not have releasability is sealed during vulcanization molding. The method for producing a tire with a sealant according to claim 1, wherein the tire is vulcanized and bonded to a wall surface of the agent chamber (6). By injection of 3. The release sheet (9 _1, 9 _2, 9 ₃₎ is sealing agent be composed of a dissolvable material in the sealant (7) sealant chamber (6) (7) The method for producing a sealant-containing tire according to claim 1, wherein the tire is dissolved. 4. The release sheet (9 ₁ , 9 ₂ , 9 ₃ ) is made of water-soluble paper or non-woven fabric.
3. The method for producing a tire containing a sealant according to item 1. 5. A plurality of release sheets (9 ₁ , 9 ₂ ,
9. The method according to claim 1, wherein 9 ₃ ) are stacked and arranged.
3. The method for producing a tire containing a sealant according to item 1. 6. The release sheet (9 ₂ ) is folded in a corrugated shape before vulcanization molding.
₂ ) The method for producing a tire with a sealant according to claim 1, wherein the method is stretched.