JP2011207166A - Method of manufacturing tire, and tire - Google Patents

Abstract

PROBLEM TO BE SOLVED: To sufficiently secure the strength of a joint part in a tire configured by jointing a plurality of tire configuration members formed of a thermoplastic material.SOLUTION: The strength of the joint part can be sufficiently secured by melting the end of one tire half body 17A and the end of the other tire half body 17A with a heated trowel 47 and welding both, then by welding the molten part of the tire half body 17A to the melted thermoplastic material 43 for welding by feeding the melted thermoplastic material 43 for welding to the welding part.

Description

  The present invention relates to a method for manufacturing a tire to be mounted on a rim, and a tire, and more particularly, to a method for manufacturing a tire at least partially formed of a thermoplastic material, and the tire.

Conventionally, pneumatic tires made of rubber, organic fiber materials, steel members, and the like are used in vehicles such as passenger cars.
However, there is a limit to the use of recycled rubber after use, and it has been disposed of by incineration and thermal recycling, crushing it and using it as road pavement material.

In recent years, it is required to use a thermoplastic resin, a thermoplastic elastomer, or the like as a tire material because of weight reduction and ease of recycling.
For example, Patent Document 1 discloses a pneumatic tire formed using a thermoplastic polymer material.

Japanese Patent Laid-Open No. 03-143701

A tire using a thermoplastic polymer material is easy to manufacture and low in cost as compared with a conventional rubber tire.
By the way, when the tire is molded by a mold, if the tire lumen is formed by the core, there is a problem that the core cannot be taken out from the molded tire. Therefore, in patent document 1, the pneumatic tire is obtained by shape | molding the semi-annular tire piece which divided | segmented the tire into the axial direction, and joining two tire pieces mutually.

The tire pieces are joined by heating the periphery of the joining portion of one tire piece and the other tire piece with a mold itself or by a high-frequency heater or the like to form a thermoplastic polymer material constituting the tire piece. This is done by melting and fluidizing.
However, once the molded tire piece is heated and melted again, the joint part is exposed to heat for a long time, and the material strength of the melted and solidified part is reduced compared to other parts due to thermal deterioration. There remains concern about the strength of the joint.

Moreover, before joining with a metal mold | die, it is difficult for the edge parts of a tire piece to overlap and overlap by 1 round with sufficient precision.
In addition, since the periphery of the joining portion is melted, the joining portion must be formed with a joining mold, and there is a problem that the number of molds increases.
Moreover, since the semi-annular tire piece joint portion is asymmetrical in order to suppress unevenness of the joint portion, there is a problem that the types of molds increase (two types of molds are required).

  The present invention has been made to solve the above-described problems, and provides a tire manufacturing method for manufacturing a tire with sufficient strength at the joint portion and a tire with sufficient strength at the joint portion. Is the purpose.

  The invention according to claim 1 is a tire manufacturing method for manufacturing a tire constituted by joining a plurality of tire constituent members formed of a thermoplastic material to each other, and the heated press heating members are connected to each other. A melting step of pressing the end of one tire constituent member and the end of the other tire constituent member to melt the end of the one tire constituent member and the end of the other tire constituent member, A separate thermoplastic material is replenished in the molten portion of the tire component, and the molten separate thermoplastic material and the molten thermoplastic material are welded, and then the thermoplastic material And a joining step of joining the one tire constituent member and the other tire constituent member by cooling and solidifying the separate thermoplastic material.

In the tire manufacturing method according to claim 1, first, in the melting step, the heated pressing heating member is pressed against the end of one tire constituent member and the end of the other tire constituent member that are connected to each other. Thereby, the edge part of one tire structural member and the edge part of the other tire structural member are fuse | melted. The portion melted by the heating of the pressing heating member is pressed by the pressing heating member, so that the surface is uniformly leveled without the thermoplastic resin expanding non-uniformly at the time of melting.
The melted portion at the end of one tire constituent member and the melted portion of the other tire constituent member are completely integrated without a boundary.

In the next joining step, the melted separate thermoplastic material is replenished to the melted portion of the tire component. Then, after the melted thermoplastic material and the melted separate thermoplastic material are welded, the thermoplastic material and the separate thermoplastic material are cooled and solidified, and one tire constituent member and the other tire configuration The member is firmly joined.
Further, since a separate thermoplastic material is replenished in the melted portion of the tire constituent member, the strength of the joined portion can be improved as compared with the case where the tire constituent member is not replenished.

  According to a second aspect of the present invention, in the tire manufacturing method according to the first aspect, in the melting step, the end portions are sequentially melted by the pressing and heating member, and in the joining step, welding is performed in the melting step. The separate thermoplastic material melted in the part is sequentially supplied, and the separate thermoplastic material is sequentially pressed by a roller.

  In the tire manufacturing method according to claim 2, the end portions are sequentially melted by the pressure heating member in the melting step, and in the joining step, separate thermoplastic materials are sequentially supplied to the portions welded in the melting step. Since the separate thermoplastic materials are sequentially pressed by the rollers, the tire constituent members can be welded efficiently. In addition, since the melted separate thermoplastic material is sequentially pressed by the roller, the melted separate thermoplastic material can be surely welded to the melted portion of the tire component member, and the separate thermoplastic material The material can be leveled flat.

  According to a third aspect of the present invention, in the tire manufacturing method according to the first or second aspect, in the melting step, the end of the one tire constituent member melted and the other tire constituent member Weld the ends.

  In the tire manufacturing method according to claim 3, the heated pressure heating member is pressed against the end of one tire constituent member and the end of the other tire constituent member that are connected to each other, and the end of one tire constituent member After the end of the other tire constituent member is melted, the end of one tire constituent member and the end of the other tire constituent member are welded together.

  According to a fourth aspect of the present invention, in the tire manufacturing method according to any one of the first to third aspects, in the melting step, an annular groove along the end is formed on the outer peripheral surface. With the inner supporting member supporting the inner peripheral surfaces of the one tire constituent member and the other tire constituent member from the inside, the molten portion is pushed into the annular groove by the pressing force of the pressing heating member, and the joining is performed. In the step, the melted separate thermoplastic material is replenished in the concave portion formed by pressing the pressing heating member.

  In the tire manufacturing method according to claim 4, in the melting step, the inner peripheral surface of one tire constituent member and the other tire constituent member is an inner support member in which an annular groove along the end portion is formed on the outer peripheral surface. The part melted by the pressing force of the pressing heating member is pushed into the annular groove in this state.

When the melted portion of the tire component member is pushed into the annular groove by the pressing force of the pressing heating member, a recess is formed in the melted portion, but in the joining process, the other thermoplastic material melted is the recess. The recess can be eliminated.
Further, since the concave portion is eliminated at the welded portion, a thinned portion is not formed at the welded portion.

  According to a fifth aspect of the present invention, in the method for manufacturing a tire according to any one of the first to fourth aspects, in the joining step, the thickness of the welded portion is equal to that of the end portion before the welding. The separate thermoplastic material melted so as to be thicker than the thickness is supplied.

  In the tire manufacturing method according to the fifth aspect, in the joining step, a melted separate thermoplastic material is supplied, and the thickness of the welded portion is formed thicker than the thickness of the end portion before welding. Thereby, the joining strength of a welding part is improved reliably.

  The invention according to claim 6 is the tire manufacturing method according to any one of claims 1 to 5, wherein the thermoplastic material and the separate thermoplastic material are the same type of thermoplastic material. It is.

  In the method for manufacturing a tire according to claim 6, since the thermoplastic material and the separate thermoplastic material are the same type of thermoplastic material, the tire constituent member and the separate thermoplastic material are separated from each other at the welded portion. Are compatible with each other and can be integrated completely.

  A seventh aspect of the present invention is the tire manufacturing method according to any one of the first to sixth aspects, further comprising a forced cooling step of forcibly cooling the welded portion after the joining step.

  In the tire manufacturing method according to claim 7, in the forced cooling step, the welded portion is forcibly cooled to rapidly solidify the molten thermoplastic material (tire constituent member) and the separate thermoplastic material. And deformation of the welded portion can be suppressed.

  The tire according to claim 8 is manufactured by the method for manufacturing a tire according to any one of claims 1 to 7.

Next, the operation of the tire according to claim 8 will be described.
It is possible to sufficiently ensure the strength of the joint portion of the tire constituent member made of the thermoplastic material.

  According to a ninth aspect of the present invention, in the tire according to the eighth aspect, the rim bead sheet includes a bead portion contacting the rim flange and a bead portion contacting the rim flange, and an annular bead core is embedded in the bead portion. Yes.

Next, the operation of the tire according to claim 9 will be described.
An annular bead core is embedded in the bead portion that is a fitting portion with the rim, and thus the tire can be firmly held against the rim in the same manner as a conventional rubber pneumatic tire.

  According to a tenth aspect of the present invention, in the tire according to the eighth or ninth aspect, at least a portion from the bead portion to an outer peripheral portion is formed of the thermoplastic material.

Next, the operation of the tire according to claim 10 will be described.
By forming the bead portion to the outer peripheral portion with a thermoplastic material, that is, by forming the bead portion from one bead portion to the other bead portion with a thermoplastic material, the ratio of the thermoplastic material in the entire tire increases and is recycled. Improves.

  The outer peripheral portion refers to a portion corresponding to the tread portion that contacts the road surface with the portion connecting the outer end in the tire radial direction of one tire side portion and the outer end in the tire radial direction of the other tire side portion. .

  The invention according to claim 11 is the tire according to any one of claims 8 to 10, wherein one tire constituent member and the other tire constituent member to be joined to each other are at the center in the tire width direction. It is joined.

Next, the operation of the tire according to claim 11 will be described.
When one tire constituent member and the other tire constituent member are joined at the center in the tire width direction, two tire constituent members having the same shape are joined face to face to form the tire constituent member. Only one type of mold is required, and more efficient manufacturing can be realized as compared with the case where one tire constituent member and the other tire constituent member have different shapes.

  A twelfth aspect of the present invention is the tire according to any one of the eighth to eleventh aspects, wherein the tire is formed by spirally winding a cord having higher rigidity than the thermoplastic material. A layer is provided on the outer periphery.

Next, the operation of the tire according to claim 12 will be described.
A reinforcing layer formed by spirally winding a cord having higher rigidity than that of the thermoplastic material is provided on the outer peripheral portion of the tire, whereby the side of the tire that contacts the road surface is reinforced. The reinforcing layer serves as a belt for a rubber pneumatic tire.
Therefore, by providing the reinforcing layer on the outer peripheral portion of the tire, the puncture resistance, fracture resistance, circumferential rigidity, creep prevention effect, and the like are improved as compared with the case where the reinforcing layer is not provided.

  According to a thirteenth aspect of the present invention, in the tire according to any one of the eighth to twelfth aspects, the thermoplastic material is provided in a portion that contacts the rim so that air in the tire does not leak to the outside. A seal portion made of a softer material is provided.

Next, the operation of the tire according to claim 12 will be described.
By providing a seal portion made of a material softer than the thermoplastic material at a portion in contact with the rim, the sealing performance (airtightness) between the tire and the rim is improved. For this reason, compared with the case where it seals with a rim | limb and a thermoplastic material, the leak of the air in a tire can be suppressed further. Moreover, rim fit property is also improved by providing a seal part.

  The invention according to claim 14 is the tire according to any one of claims 8 to 13, wherein the rubber in contact with the road surface is more excellent in wear resistance than the separate thermoplastic material. A tread rubber layer is provided.

Next, the operation of the tire according to the fourteenth aspect will be described.
By providing a tread rubber layer made of rubber with better abrasion resistance than thermoplastic materials in the part that comes in contact with the road surface, compared to the case where no rubber is provided in the part that comes in contact with the road surface, wear resistance, Destruction resistance is improved.

  According to the tire manufacturing method of the first aspect, it is possible to efficiently manufacture a tire in which the strength of the joint portion of the tire constituent member made of the thermoplastic material is sufficiently ensured.

  According to the tire manufacturing method of the second aspect, it is possible to efficiently manufacture a tire having high bonding strength.

  According to the tire manufacturing method of the third aspect, in the melting step before the joining step, one tire constituent member and the other tire constituent member can be welded in advance.

  According to the method for manufacturing a tire according to claim 4, the separate thermoplastic material can be leveled, and the separate thermoplastic material can be reliably adhered to the surface of the tire constituent member. it can.

  According to the tire manufacturing method of the fifth aspect, the bonding strength can be further increased, and the tire performance such as uniformity can be improved.

  According to the tire manufacturing method of the sixth aspect, the bonding strength can be further increased.

  According to the tire manufacturing method of the seventh aspect, the separate thermoplastic material can be quickly solidified, and the separate thermoplastic material can be prevented from being lifted or deformed.

  Since the tire according to claim 8 is manufactured by the method for manufacturing a tire according to any one of claims 1 to 7, sufficient strength of a joining portion of a tire constituent member made of a thermoplastic material is ensured. It has the excellent effect of being able to.

  Since the tire according to claim 9 is configured as described above, the tire can be firmly held against the rim.

  Since the tire according to claim 10 has the above-described configuration, the ratio of the thermoplastic material in the entire tire is increased, and the recyclability is improved.

  Since the tire according to the eleventh aspect has the above-described configuration, efficient manufacture can be realized.

  Since the tire according to the twelfth aspect has the above-described configuration, the puncture resistance, the fracture resistance, the circumferential rigidity, the creep preventing effect, and the like can be improved as compared with the case where the reinforcing layer is not provided.

  Since the tire according to the thirteenth aspect has the above-described configuration, air leakage in the tire can be further suppressed, and the rim fit property can be improved.

  Since the tire according to the fourteenth aspect has the above configuration, it is possible to improve wear resistance and fracture resistance.

(A) is the perspective view which made some tires the section concerning one embodiment of the present invention in section, and (B) is the sectional view of the bead part with which the rim was equipped. It is a perspective view of a molding machine. (A) is a perspective view of the tire support part made into the minimum diameter, (B) is a perspective view of the tire support part made into the maximum diameter. It is a perspective view of a molding machine and an extruder. (A) is a perspective view of a hot water bath, (B) is a side view of a hot water bath, a resin discharge nozzle, and a leveling roller. It is a perspective view which shows the principal part of a cord supply apparatus. It is an expanded sectional view of the joined part of a tire half body. It is a perspective view of the tire support part which supported the tire half and the tire inner surface support ring. (A)-(D) are sectional drawings of the joining part periphery which shows the joining process of a tire half body. (A), (B) is sectional drawing which shows joining of the tire half body which concerns on a comparative example. It is a disassembled perspective view of the tire case and tread rubber layer concerning other embodiments.

Below, the tire concerning one embodiment of the tire of the present invention is explained according to a drawing. As shown in FIG. 1, the tire 10 of the present embodiment has a cross-sectional shape substantially similar to that of a conventional general rubber pneumatic tire.
The tire 10 includes a bead seat portion 21 of the rim 20, a pair of bead portions 12 that contact the rim flange 22, a side portion 14 that extends outward from the bead portion 12 in the tire radial direction, and an outer side in the tire radial direction of one side portion 14. A tire case (tire frame member) 17 including a crown portion 16 that connects the end and an outer end in the tire radial direction of the other side portion 14 is provided.

The tire case 17 of the present embodiment is formed of a first thermoplastic material.
The tire case 17 according to the present embodiment is an annular, tire-constituting member in which one bead portion 12, one side portion 14, and a half-width crown portion 16 are integrally formed by molding or the like. The tire halves 17A face each other and are joined at the tire equatorial plane, and form an air chamber with the rim. The tire case 17 is not limited to one formed by joining two members. For example, the tire case 17 corresponds to a first member integrated with one bead portion 12 and the side portion 14 and a tread portion (tire outer peripheral portion). Three or more members such as a second member to be combined and a third member in which the other bead portion 12 and the side portion 14 are integrated may be formed, and one pair of bead portions 12 and one pair may be formed. The side part 14 and the crown part 16 may be integrally formed.

  Further, a reinforcing material (polymer material, metal fiber, cord, nonwoven fabric, woven fabric, etc.) is embedded in the tire case 17 (for example, the bead portion 12, the side portion 14, the crown portion 16 and the like), and the reinforcing material is provided. The tire case 17 may be reinforced.

  As the first thermoplastic material, a thermoplastic resin, a thermoplastic elastomer (TPE), or the like can be used, but a thermoplastic elastomer should be used in consideration of elasticity required during running and moldability during manufacturing. Is preferred.

Examples of the thermoplastic elastomer include amide-based thermoplastic elastomer (TPA), ester-based thermoplastic elastomer (TPC), olefin-based thermoplastic elastomer (TPO), styrene-based thermoplastic elastomer (TPS) specified in JIS K6418, Examples thereof include urethane-based thermoplastic elastomer (TPU), crosslinked thermoplastic rubber (TPV), and other thermoplastic elastomers (TPZ). In particular, TPV partially kneaded with rubber-based resin is preferable.
Examples of the thermoplastic resin include urethane resin, olefin resin, vinyl chloride resin, polyamide resin, and the like.

  As these thermoplastic materials, for example, the deflection temperature under load specified at ISO 75-2 or ASTM D648 (at the time of 0.45 MPa load) is 78 ° C. or more, the tensile yield strength specified by JIS K7113 is 10 MPa or more, Similarly, the tensile yield elongation specified in JIS K7113 is 10% or more, the tensile breaking elongation specified in JIS K7113 (JIS K7113) is 50% or more, and the Vicat softening temperature (Method A) specified in JIS K7206 is 130 °. What is C or more can be used.

  The tire half body 17A made of the first thermoplastic material can be molded by, for example, vacuum molding, pressure molding, injection molding, melt casting, etc., and manufactured as compared with the case of molding (vulcanizing) with rubber. The process can be greatly simplified and the molding time can be shortened.

  In the present embodiment, the tire half body 17A has a bilaterally symmetric shape, that is, one tire half body 17A and the other tire half body 17A have the same shape, and therefore a mold for molding the tire half body 17A. There is an advantage that only one type is required.

  An annular bead core 18 made of a steel cord is embedded in the bead portion 12 of the present embodiment, as in a conventional general pneumatic tire, but the rigidity of the bead portion 12 is secured, and the bead portion 12 is fitted with the rim 20. If there is no problem, the bead core 18 may be omitted. The bead core 18 may be formed of a cord or material other than steel, such as an organic fiber cord.

  In this embodiment, the contact portion of the bead portion 12 with the rim 20 and at least the portion of the rim 20 that contacts the rim flange 22 are excellent in sealing performance (air tightness), which is a softer material than the first thermoplastic resin. An annular sealing layer 24 made of rubber is formed. This sealing layer 24 may also be formed in a portion that contacts the bead sheet. As the rubber forming the seal layer 24, it is preferable to use the same type of rubber as that used on the outer surface of the bead portion of a conventional general rubber pneumatic tire. If the sealing property (airtightness) between the rim 20 can be secured with only the thermoplastic resin, the rubber seal layer 24 may be omitted, and the seal is better than the first thermoplastic resin forming the side portion 14. Other types of thermoplastic resins having excellent properties (airtightness) may be used.

A crown portion reinforcing layer 28 made of a steel reinforcing cord 26 wound in a spiral shape is embedded in the crown portion 16. Note that the entire reinforcing cord 26 may be embedded in the crown portion 16, or a part thereof may be embedded in the crown portion 16. The crown portion reinforcing layer 28 corresponds to a belt disposed on the outer peripheral surface of the carcass of a conventional rubber pneumatic tire.
It is also possible to form the crown portion reinforcing layer 28 by covering the reinforcing cord 26 with a resin material and winding the reinforcing cord 26 covered with the resin material around the crown portion 16. In this case, the resin material that covers the reinforcing cord 26 is joined to the crown portion 16 by welding or adhesion at the contact portion with the crown portion 16.

  The embedment amount of the reinforcing cord 26 is preferably 1/5 or more of the diameter of the reinforcing cord 26, and more preferably more than 1/2. Most preferably, the entire reinforcing cord 26 is embedded in the crown portion 16. When the embedment amount of the reinforcing cord 26 exceeds 1/2 of the diameter of the reinforcing cord 26, the reinforcing cord 26 is difficult to jump out of the surface due to its size. Further, when the entire reinforcing cord 26 is embedded in the crown portion 16, the surface becomes flat and it is difficult for air to enter even if a member is placed thereon.

  A tread rubber layer 30 made of rubber having higher abrasion resistance than the first thermoplastic material forming the side portion 14 is disposed on the outer peripheral side of the crown portion reinforcing layer 28. The rubber used for the tread rubber layer 30 is preferably the same type of rubber as that used for conventional rubber pneumatic tires. In addition, you may provide the tread layer which consists of another kind of thermoplastic material which is more excellent in abrasion resistance than the 1st thermoplastic material which forms the side part 14 in an outer peripheral part.

(Tire manufacturing equipment)
Next, the manufacturing apparatus of the tire 10 of this embodiment is demonstrated.
FIG. 2 is a perspective view showing the main part of the molding machine 32 used when forming the tire 10. In the molding machine 32, a geared motor 37 that rotates a horizontally disposed shaft 36 is attached to an upper portion of a pedestal 34 that is grounded to a floor surface.

A tire support portion 40 is provided on the end portion side of the shaft 36. The tire support 40 includes a cylinder block 38 fixed to the shaft 36, and a plurality of cylinder rods 41 extending radially outward are provided at equal intervals in the circumferential direction.
A tire support piece 42 having an arcuate curved surface 42A whose outer surface is set substantially equal to the radius of curvature of the tire inner surface is provided at the tip of the cylinder rod 41.

2 and 3A show a state where the protruding amount of the cylinder rod 41 is the smallest (the tire support portion 40 has a minimum diameter), and FIG. 3B shows the protruding amount of the cylinder rod 41. The largest state (the state where the tire support portion 40 has the maximum diameter) is shown.
Each cylinder rod 41 can move in the same direction in the same direction.

  As shown in FIG. 4, in the vicinity of the molding machine 32, an extruder 44 for extruding a welding thermoplastic material (a separate thermoplastic material of the present invention) 43 is arranged. The extruder 44 includes a resin discharge nozzle 46 for discharging the molten thermoplastic material 43 for welding downward.

  The welding thermoplastic material 43 is preferably the same type as the first thermoplastic material constituting the tire case 17, but may be of a different type as long as it can be welded. If the same kind of material is used, the tire case 17 as a whole can be made of one kind of thermoplastic material, so that the cost is low. Moreover, if it is set as a different material, it can be set as the material which has a preferable characteristic with respect to each of the 1st thermoplastic material for tire frame members, and the welding thermoplastic material 43 for joining.

  Moreover, the thermoplastic material 43 for welding has a Young's modulus within the range of 0.1 to 10 times that of the first thermoplastic material. If the Young's modulus is 10 times or less, there is no problem in the rim assembling property, but if it exceeds 10 times, the tire crown part becomes too hard, and if the rim is forcibly assembled, the welded part may break. On the other hand, if the Young's modulus is less than 0.1 times, the welding thermoplastic material 43 is too soft, and only the center portion extends in the tire width direction due to the tension in the tire width direction that occurs in the tire during internal pressure filling, so that the tire 10 There is a risk of deformation.

  In the vicinity of the resin discharge nozzle 46, the welding thermoplastic material 43 adhered to the outer surface of the tire is pressed against the downstream side in the rotation direction of the tire case 17 (arrow A direction side) to level the roller 48 and the leveling roller. A cylinder device 50 that moves the roller 48 in the vertical direction is disposed. The cylinder device 50 is supported by the support column 52 of the extruder 44 through a frame (not shown).

  In the leveling roller 48 of the present embodiment, cooling water is circulated inside the roller and is cooled by the cooling water. In order to cool the leveling roller 48 with water, the inside of the leveling roller 48 and the shaft have a hollow structure, pipes are connected to both ends of the shaft via rotary joints, and cooling water is supplied to the inside of the roller from one rotary joint side. Then, the used cooling water may be discharged from the other rotary joint side.

  A cooling air ejection nozzle 45 that ejects cooling air is disposed downstream of the leveling roller 48 in the tire frame member rotation direction.

A hot metal rod 47 is disposed on the side opposite to the tire case rotation direction side of the resin discharge nozzle 46 (the direction opposite to the arrow A direction).
As shown in FIG. 5, the hot iron 47 is made of a metal material, and an electric heater (not shown) is built therein. The hot metal bowl 47 of the present embodiment has a plate shape as a whole, and a rib 47 </ b> A that is parallel to the tangential direction of the outer peripheral surface of the drum 22 is formed on the lower surface. The hot iron 47 can be heated to a temperature equal to or higher than the melting point of the thermoplastic material.

  As shown in FIGS. 4 and 5, a cylinder device 51 that moves the hot iron 47 in the vertical direction is disposed above the hot iron 47. The cylinder device 51 is supported on the support column 52 of the extruder 44 through a frame (not shown).

The extruder 44 is movable in a direction parallel to the shaft 36 of the molding machine 32 along the guide rail 54 arranged on the floor surface.
As shown in FIG. 6, a cord supply device 56 including a reel 58, a cord heating device 59, and the like is movably mounted on the guide rail 54.

  The cord supply device 56 includes a reel 58 around which the reinforcing cord 26 is wound, a cord heating device 59 disposed on the downstream side of the reel 58 in the code conveying direction, a first roller 60 disposed on the downstream side of the reinforcing cord 26 in the conveying direction, A first cylinder device 62 that moves the first roller 60 in a direction that is in contact with and away from the outer peripheral surface of the tire; a second roller 64 that is disposed on the downstream side in the conveying direction of the reinforcing cord 26 of the first roller 60; And a second cylinder device 66 that moves the second roller 64 in a direction in which the second roller 64 comes in contact with and separates from the tire outer peripheral surface. The code supply device 56 only needs to be provided with either the first roller 60 or the second roller 64.

  Further, the cord heating device 59 discharges the heated reinforcing cord 26 and a heater and a fan (not shown) that generate hot air, a heating box 68 in which the hot cord is supplied and the reinforcing cord 26 passes through the internal space. A discharge unit 70 is provided.

(Tire manufacturing method)
(1) As shown in FIG. 2, first, two tire halves 17A are arranged facing each other on the outer peripheral side of the tire support portion 40 with a reduced diameter, and inside the two tire halves 17A, A cylindrical tire inner surface support ring 72 made of a thin metal plate (for example, a steel plate having a thickness of 0.5 mm) is disposed (In FIG. 2, one tire half body 17A is removed to show the inside. ing.).

  As shown in the cross-sectional view of FIG. 7, the tire half body 17A of the present embodiment has a tapered shape on the tire equatorial plane CL side. In the tire half body 17A of the present embodiment, the inner peripheral surface is flat on the tire equatorial plane side (parallel to the tire rotation axis), and the tire diameter increases toward the end on the tire equatorial plane CL side on the outer peripheral surface. An outer inclined surface 17Aa is formed in the direction of decreasing.

  In the present embodiment, when the two tire halves 17A are arranged facing each other, the end of one tire half 17A and the end of the other tire half 17A are brought into contact with each other, A slight gap may be opened.

  The outer diameter of the tire inner surface support ring 72 is set to be approximately the same as the inner diameter of the outer peripheral portion of the tire half body 17A, and the outer peripheral surface of the tire inner surface support ring 72 is the inner peripheral surface of the outer peripheral portion of the tire half body 17A. It comes to adhere to.

  As shown in FIGS. 7 and 8, an annular groove 72 </ b> A that extends continuously along the circumferential direction is formed in the center in the width direction on the outer circumferential surface of the tire inner surface support ring 72. The annular groove 72A of the present embodiment has a substantially semicircular cross section, but may have a shape other than a semicircular shape.

By disposing the cylindrical tire inner surface support ring 72 inside the two tire half bodies 17A, the inner surface side of the joint portion between the tire half bodies 17A comes into close contact with the outer peripheral surface of the tire inner surface support ring 72, and the tire support portion Generation of unevenness (reverse shape of the unevenness) of the joining portion (described later) due to unevenness in the tire circumferential direction generated on the outer periphery of the tire support portion due to the gap (recessed portion) between the 40 tire support pieces 42 and the tire support piece 42 It is possible to suppress the unevenness in the tire circumferential direction of the tire case 17 itself.
Since the tire inner surface support ring 72 is formed of a thin metal plate, the tire inner surface support ring 72 can be easily deformed by bending and inserted into the tire half body 17A.

  Then, as shown in FIG. 8, the diameter of the tire support portion 40 is enlarged, a plurality of tire support pieces 42 are brought into contact with the inner peripheral surface of the tire inner surface support ring 72, and the tire inner surfaces are formed by the plurality of tire support pieces 42. The support ring 72 is held from the inside (in FIG. 8, both the tire halves 17A are removed to show the inside). When the back side of the annular groove 72A has a convex shape on the inner peripheral surface of the tire inner surface support ring 72, a groove may be formed on the outer peripheral surface of the tire support piece 42 so as to escape the convex shape.

In the present embodiment, the tire inner surface support ring 72 is formed of a thin metal plate in order to bend and deform, but the tire inner surface support ring 72 may be a hollow rigid body.
Since the two tire halves 17A are supported so as to face each other in this way, the ends on the tire equatorial plane side of the tire halves 17A can be accurately aligned by one round.

(2) Next, the extruder 44 is moved, and as shown in FIG. 4, the butted portions of the two tire halves 17A (the tire equatorial plane CL of the tire case 17) The nozzle 46, the leveling roller 48, and the cooling air jet nozzle 45 are disposed below.

(3) Next, the hot iron 47 and the leveling roller 48 are lowered. The hot iron 47 is lowered from the state shown in FIG. 9 (A), and the hot iron 47 is pressed against the outer periphery of the abutting portion of the two tire halves 17A as shown in FIG. 9 (B).

(4) A portion where the tire case 17 supported by the tire support portion 40 is pressed by the hot rod 47 while rotating in the direction of arrow A, that is, an end portion of one tire case 17 and an end portion of the other tire case 17 Are sequentially melted, and the end portions are successively welded without causing a boundary (in FIG. 9, the halftone dot portions are melted).
In the present embodiment, since the hot iron 47 having the rib 47A formed on the lower surface is pressed against the welded portion, the melted portion is in close contact with the annular groove 72A, and the welded portion surface is along the circumferential direction. Thus, a recess is formed.

(5) Due to the rotation of the tire support portion 40, the melted portion moves to the downstream side in the rotational direction (arrow A direction side), and the molten thermoplastic material 43 for welding that is pushed out from the resin discharge nozzle 46 is welded. Sequentially supplied to the parts. As a result, the melted portion of the tire case 17 and the molten thermoplastic material 43 for welding are completely welded without causing a boundary, and the concave portion disappears completely at the welded portion, and FIG. As shown in the figure, the gentle convex portion is formed by the molten thermoplastic material 43.

(6) After that, as shown in FIG. 9D, the molten thermoplastic material 43 for welding is sequentially pressed from the radially outer side to the inner side by the leveling roller 48, and the surface is leveled almost flat. The
Thus, in the tire manufacturing method of the present embodiment, after the one tire half 17A and the other tire half 17A are completely welded, the welded thermoplastic material 43 in a molten state is further welded to the welded portion. Since the thickness of the welded portion is increased, a high bonding strength is obtained, and in particular, it is strong against bending deformation and tension.

  In addition, in the tire half body 17A before bonding, it is preferable to wash the bonded portion with a solvent such as alcohol. Further, in the tire half body 17A before bonding, a corona treatment, an ultraviolet treatment, or the like may be performed on the joining portion so that the welding thermoplastic material 43 is easily attached.

  Thereafter, the welding thermoplastic material 43 adhering to the tire half 17A is solidified, the one tire half 17A and the other tire half 17A are firmly joined, and the two tire halves 17A are completely integrated. A tire case 17 is obtained.

  In the present embodiment, the welded portion is quickly cooled and solidified by bringing the water-cooled leveling roller 48 into contact with the welded portion and applying cooling air ejected from the cooling air ejection nozzle 45. . The welded portion can be solidified by natural cooling, but if it takes a long time to solidify, the welded portion may be deformed.

  Therefore, in order to suppress deformation and the like after welding, in this embodiment, forced cooling of the welded portion is performed using the water-cooled leveling roller 48 and the cooling air ejected from the cooling air ejection nozzle 45. Yes. Instead of the cooling air jet nozzle 45, a water-cooled leveling roller 48 may be additionally provided.

(7) Next, the extruder 44 is retracted, and the cord supply device 56 is disposed in the vicinity of the tire support portion 40.
As shown in FIG. 6, the tire case 17 is rotated in the direction of arrow A, and the heated reinforcing cord 26 discharged from the discharge portion 70 of the cord supply device 56 is spirally wound around the outer peripheral surface of the tire case 17. A partial reinforcing layer 28 is formed. In order to wind the reinforcing cord 26 around the outer circumferential surface of the tire case 17, the cord supply device 56 may be moved in the axial direction of the tire case 17 while the tire case 17 is rotated.

  The reinforcing cord 26 is heated to a temperature higher than the melting point of the first thermoplastic material (for example, the temperature of the reinforcing cord 26 is heated to about 100 to 200 ° C.), so that the first portion of the portion where the reinforcing cord 26 is in contact is heated. The thermoplastic material is melted, and a part or the whole of the reinforcing cord 26 can be embedded in the outer peripheral surface of the tire case 17.

In the present embodiment, the reinforcing cord 26 is pressed by the first roller 60 and the second roller 64 and embedded in the first thermoplastic material.
The embedment amount of the reinforcing cord 26 can be adjusted by the temperature of the reinforcing cord 26, the tension applied to the reinforcing cord 26, and the like. The tension applied to the reinforcing cord 26 can be adjusted by, for example, applying a brake to the reel 58, or providing a tension adjusting roller in the middle of the conveying path of the reinforcing cord 26.

(8) Next, the vulcanized belt-like tread rubber layer 30 is wound around the outer peripheral surface of the tire case 17 by one turn, and the tread rubber layer 30 is attached to the outer peripheral surface of the tire case 17 with an adhesive or unvulcanized rubber ( When unvulcanized rubber is used, vulcanization for bonding is performed in a later step.) In addition, the tread rubber layer 30 can use the precure tread used for the retread tire conventionally known, for example. This step is the same step as the step of bonding the precure tread to the outer peripheral surface of the base tire of the retreaded tire.

  As the adhesive, a triazine thiol adhesive, a chlorinated rubber adhesive, a phenol resin adhesive, an isocyanate adhesive, a halogenated rubber adhesive, or the like can be used. In order to improve the adhesive strength, it is preferable that the adhesive is applied and then dried to some extent. For this reason, when apply | coating an adhesive agent, it is preferable to carry out in the atmosphere of 70% or less of humidity.

  Further, it is preferable that the portion to which the tread rubber layer 30 is bonded is previously buffed to roughen the surface and washed with a solvent such as alcohol. Further, in the tire half body 17A before bonding, a corona treatment, an ultraviolet treatment, or the like may be performed on the joining portion so that the welding thermoplastic material 43 is easily attached.

(9) When the seal layer 24 made of vulcanized rubber is bonded to the bead portion 12 of the tire case 17 using an adhesive or the like, the tire 10 shown in FIG. 1 is completed.
(10) Finally, the diameter of the tire support portion 40 is reduced, the completed tire 10 is removed from the tire support portion 40, the internal tire inner surface support ring 72 is bent and deformed, and is removed from the tire.

(Function)
Next, the effect | action of the tire 10 of this embodiment is demonstrated.
In the tire 10 of the present embodiment, one tire half 17A and the other tire half 17A are welded in advance at the joining portion of the tire half 17A, and a welding thermoplastic material 43 is further welded to the welded portion. Therefore, high joint strength is obtained.

  It is to be noted that, by welding the welded thermoplastic material 43 to the melted first thermoplastic material, the affinity (phase) of the welded thermoplastic material 43 with respect to the first thermoplastic material. As compared with the case where the first thermoplastic material is not melted, a high bonding strength is obtained between the first thermoplastic material and the welding thermoplastic material 43. For example, as shown in FIG. 10 (A), the unmelted end of one member 100 and the unmelted end of the other member 102 are arranged at an interval, and FIG. 10 (B) As shown, when the thermoplastic material 104 melted between the ends and around the ends is adhered and solidified, the corner portions of the end portions of the members remain inside the joint portions, and thus a large stress is generated. When acting, the corner portion becomes a fracture nucleus and is easily broken from the corner portion.

In the present embodiment, the end portion of the tire half body 17A is melted, but since the welding thermoplastic material 43 is adhered and immediately cooled, deterioration of the first thermoplastic material is suppressed. Yes.
In the present embodiment, the tire half 17A having the same shape is opposed to each other to form the tire case 17, so that only one type of mold for molding the tire half 17A is required. That is, the symmetrical tire 10 can be manufactured without changing the shape of the mold between the one tire half 17A and the other tire half 17A.

In the tire 10 of the present embodiment, since the substantially entire portion excluding the tread portion is formed of the first thermoplastic material, it can be formed by vacuum forming, pressure forming, injection forming, etc., and compared with a rubber pneumatic tire. Thus, the manufacturing process can be greatly simplified.
In the tire 10 of this embodiment, since the bead core 18 is embedded in the bead portion 12, the fitting strength with respect to the rim 20 can be ensured similarly to the conventional rubber pneumatic tire.

  In the tire 10 of the present embodiment, the ratio of the first thermoplastic material in the tire constituent material is large, and thus the recyclability is good.

By providing the crown portion 16 with the crown portion reinforcing layer 28 formed by spirally winding the reinforcing cord 26 having higher rigidity than the first thermoplastic material, the crown portion 16 is reinforced and puncture resistance is improved. In addition, the fracture resistance, the circumferential rigidity, the creep prevention effect, etc. are improved.
Since a seal layer 24 made of rubber having a sealing property (air tightness) superior to that of the first thermoplastic material is provided on a portion that contacts the rim 20, particularly a portion that contacts the rim flange 22, a conventional rubber The same sealing performance as that of a pneumatic tire made of steel can be obtained.

The tire 10 of the present embodiment is provided with a tread rubber layer 30 made of the same kind of rubber as that used in the tread of a conventional rubber pneumatic tire, so that it is equivalent to a conventional rubber pneumatic tire. Wear resistance, grip and the like can be obtained.
Although the tire case 17 of the present embodiment is formed by joining two tire halves 17A, when the tire case 17 is composed of three members, the tire case 17 includes one side portion 14, the other side portion 14, And it can be divided into three members of a substantially cylindrical crown portion 16. When these are joined, they can be welded in the same manner as in this embodiment. In addition, it is preferable to arrange | position the junction part of the side part 14 and the crown part 16 in the site | part which does not contact a road surface.

[Other Embodiments]
In the above embodiment, the end portion of the tire half body 17A on the tire equatorial plane side has an acute-angle shape. However, since the end portion is melted by the hot iron 47 at the time of welding, another shape may be used.
In the above-described embodiment, the end shape of one tire half 17A and the end shape of the other tire half 17A are bilaterally symmetric with respect to the tire equatorial plane CL. good.

The end portion of the tire half body 17A is not limited to the shape described in the above embodiment, and various modifications can be made without departing from the gist of the present invention.
In the above embodiment, the tread portion is formed by winding the vulcanized belt-like tread rubber layer 30 around the outer peripheral surface of the tire case 17 to form a tread portion. However, as shown in FIG. The used tread rubber layer 30 may be inserted from the axial direction of the tire case 17 and the tire case 17 and the vulcanized tread rubber layer 30 formed in an annular shape may be bonded using an adhesive or the like.

  In the above embodiment, the material of the reinforcing cord 26 is steel, but organic fiber or the like may be used. When the reinforcing cord 26 is an organic fiber, the reinforcing cord 26 can be wound without heating the reinforcing cord 26 itself or heating and melting the outer surface of the outer periphery of the tire case 17 while heating. Is preferable from the viewpoint of bonding.

Also in this case, it is preferable to heat the joining surfaces (joining with hot air or rolling a hot roll) before joining.
In addition, although it is easy to manufacture the crown portion reinforcing layer 28 by spirally winding the reinforcing cord 26, the cord may be discontinuous in the tire width direction.

  In order to melt the end portion of the tire half body 17A, the hot metal rod 47 having the shape shown in the figure is used in the above embodiment. However, the present invention is not limited thereto, and another member other than the hot metal rod 47 may be used as long as the end of the tire half body 17A can be melted.

  In the step (4) of the tire manufacturing method of the above embodiment (the melting step of the present invention), the end of one tire case 17 and the end of the other tire case 17 are sequentially melted with a hot metal 47. Although the end portion of one tire case 17 and the end portion of the other tire case 17 were welded, the welding thermoplastic material 43 is then supplied to the melted portion of the tire case 17, so in the step (4), Only the end of the tire case 17 is melted, and welding is not necessary. Even if there is a gap between the end portion of one tire case 17 and the end portion of the other tire case 17, the gap is completely filled by supplying the thermoplastic material 43 for welding. The end of the case 17 and the end of the other tire case 17 are welded without any problem.

10 tire 12 bead portion 14 side portion (tire side portion)
16 Crown (outer periphery)
17 Tire case 17A Tire half (thermoplastic material)
17Aa Outer inclined surface (end)
18 Bead core 24 Seal layer (seal part)
26 Reinforcement cord (cord)
28 Crown reinforcement layer (reinforcement layer)
30 tread rubber layer 43 thermoplastic material for welding (separate thermoplastic material)
46 Nozzle 46 Nozzle for resin discharge 47 Hot water (pressing heating member)
48 rollers 72 tire inner surface support ring (inner support member)
72A annular groove 86 tire 88 tube 88A tube half

Claims (14)

A tire manufacturing method for manufacturing a tire configured by joining a plurality of tire constituent members formed of a thermoplastic material,
The heated pressure heating member is pressed against the end of one tire constituent member and the end of the other tire constituent member that are connected to each other, and the end of the one tire constituent member and the end of the other tire constituent member are A melting step for melting;
After the molten separate thermoplastic material is replenished to the melted portion of the tire component member, the molten separate thermoplastic material and the molten thermoplastic material are welded, and then the heat A joining method of joining the one tire constituent member and the other tire constituent member by cooling and solidifying the thermoplastic material and the separate thermoplastic material. In the melting step, the end portions are sequentially melted by the pressure heating member,
2. The tire according to claim 1, wherein, in the joining step, the separate thermoplastic material melted to a portion welded in the melting step is sequentially supplied, and the separate thermoplastic material is sequentially pressed by a roller. Manufacturing method.   The tire manufacturing method according to claim 1 or 2, wherein, in the melting step, an end portion of the one tire constituent member melted and an end portion of the other tire constituent member are welded. In the melting step, the inner circumferential surface of the one tire constituent member and the other tire constituent member is supported from the inner side by an inner supporting member in which an annular groove along the end portion is formed on the outer peripheral surface. Push the melted part into the annular groove with the pressing force of the pressing heating member,
The tire manufacturing method according to any one of claims 1 to 3, wherein, in the joining step, the melted thermoplastic material is supplemented to a recess formed by pressing of the pressing and heating member. .   The said separate thermoplastic material melt | dissolved so that the thickness of the welded part may be formed thicker than the thickness of the said edge part before welding is supplied in the said joining process. 5. The method for producing a tire according to any one of 4 above.   The tire manufacturing method according to any one of claims 1 to 5, wherein the thermoplastic material and the separate thermoplastic material are the same kind of thermoplastic material.   The tire manufacturing method according to any one of claims 1 to 6, further comprising a forced cooling step of forcibly cooling the welded portion after the joining step.   A tire manufactured by the method for manufacturing a tire according to any one of claims 1 to 7.   The tire according to claim 8, further comprising a bead portion that contacts a rim bead sheet and a rim flange on an inner side in a tire radial direction, and an annular bead core embedded in the bead portion.   The tire according to claim 8 or 9, wherein at least a part from the bead part to an outer peripheral part is formed of the thermoplastic material.   The tire according to any one of claims 8 to 10, wherein one tire constituent member and the other tire constituent member joined to each other are joined at a central portion in the tire width direction.   The reinforcing layer formed by winding a cord having rigidity higher than that of the first thermoplastic material in a spiral shape is provided on the outer peripheral portion. Tires.   The seal portion made of rubber having better sealing performance than the thermoplastic material is provided at a portion in contact with the rim so that air in the tire does not leak to the outside. The tire according to claim 1.   The tire according to any one of claims 8 to 13, wherein a tread rubber layer made of rubber having higher wear resistance than the thermoplastic material is provided at a portion in contact with a road surface.

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