JP2011207153A - Method of manufacturing tire, and tire - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method of manufacturing a tire, which stably keeps the form of tread rubber when manufacturing the tire by bonding the tread rubber to a tire frame member, and to provide a tire.SOLUTION: The tire frame member 12 is formed, vulcanized or partially vulcanized tread rubber 16 is disposed on the outside of the tire diametric direction of an outer periphery 12A of the tire frame member 12. The tread rubber 16, cushion rubber 14 and the tread rubber 16 side of at least tire frame member 12 are covered with an envelope to press the tread rubber 16 to the tire frame member 12 to form a temporary assembly. The temporary assembly is contained in a vessel to perform vulcanization by heating the vessel. The interior of the envelope is sucked in a state that a pressing member is stored in a recessed part between the envelope and the tread rubber 16.

Description

  The present invention relates to a tire manufacturing method and a tire.

  Conventionally, pneumatic tires made of rubber, organic fiber materials, steel members, and the like are used in vehicles such as passenger cars. In recent years, it has been required to use a thermoplastic material such as a thermoplastic elastomer or a thermoplastic resin for the tire frame member because of weight reduction and ease of recycling. For example, Patent Document 1 discloses a pneumatic tire formed using a thermoplastic polymer material.

  In order to manufacture a tire frame member made of such a thermoplastic material, a large and expensive vulcanizing apparatus and tire size can be obtained by integrating the tire frame member and the tread rubber using a vulcanization mold. Various molds corresponding to the above are required. Further, it is necessary that the shape of the tread rubber be stably maintained in a state where the tire frame member and the tread rubber are integrated.

  By the way, the tread rubber is removed from the used tire to form a base tire (tire frame member), and a tread pattern is formed in advance on the tread pattern side on the crown portion of the base tire (tire frame member). A technique is known in which rubber is disposed and a so-called retreaded tire is obtained by pressing and adhering tread rubber to a tire frame member while reducing the pressure in the envelope.

  For example, Patent Document 2 describes a tire retreading method in which a gas vent sheet covering the surface of a precure tread is disposed between the precure tread and the envelope, and the inside of the envelope is sucked through the gas vent sheet. ing. Patent Document 3 describes a technique in which a sheet-like fiber body surrounding an exhaust hole is integrally provided on the inner peripheral surface of a vulcanization envelope, and the inside of the envelope is sucked.

JP-A-3-143701 JP 2007-331152 A JP 2009-143099 A

  The vulcanized tread rubber affixed to the tire frame member has a relatively thin portion formed by, for example, a circumferential groove or a width direction groove (hereinafter referred to as a “dent”). There may be. For example, in a tire for a passenger car, the tread rubber is thinner than the tire used for a bus or truck, the tire used for an aircraft, or the like due to the recessed portion such as the circumferential groove or the width groove described above. Many have parts. When such a tread rubber is disposed on the tire frame member (base tire) and sucked in the envelope, the rubber in the thin portion may be deformed.

  In particular, in the vicinity of the suction valve (cap portion), the tread rubber is sucked locally and strongly. For this reason, it is desired to suppress the deformation of the tread rubber.

  In consideration of the above facts, the present invention stably maintains the shape of the tread rubber when the tire is manufactured by bonding the tread rubber to the tire frame member, and the shape of the tread rubber is stable. The object is to obtain a maintained tire.

  In the invention according to claim 1 (tire manufacturing method), the tire frame member is vulcanized or semi-cured on the outer side in the tire radial direction and a part of the dent is configured on the outer side in the tire radial direction. A tread rubber having a thin wall portion is arranged by the cover, and the tread rubber and at least the tread rubber side of the tire frame member are covered with a covering member to form a temporary assembly, and the inside of the covering member is sucked through a valve. Then, the tread rubber is pressed against the tire frame member, the temporary assembly is accommodated in a container, and the container is heated, whereby the tread rubber is bonded to the tire frame member by the tire manufacturing method. A covering member is formed by disposing a pressing member capable of pressing the thin portion from the outer side in the tire radial direction toward the tire frame member at least in a part of the recess. To suck the inside.

  In this tire manufacturing method, a tire is manufactured by adhering a tread rubber to a tire frame member without using a vulcanization mold that requires a large and expensive vulcanizer or various molds according to the tire size. Can be manufactured. For this reason, tread rubber is adhere | attached on a tire frame | skeleton member, and the manufacturing cost at the time of manufacturing a tire (a retread tire is included) can be reduced.

  In addition, when sucking the inside of the covering member, a pressing member that supports the thin portion from the outside in the tire radial direction is disposed in at least a part of the recessed portion of the tread rubber, and the thin portion is supported from the outside in the tire radial direction. Yes. Accordingly, deformation of the thin portion during suction is suppressed, and the shape of the tread rubber can be stably maintained.

  According to a second aspect of the present invention, in the first aspect of the present invention, the pressing member is disposed in the recess at least at a position radially inward with respect to the valve.

  In this way, since the suction is performed in the covering member in a state where the pressing member is disposed in the recessed portion at least on the inner side in the tire radial direction with respect to the valve, the shape of the vicinity of the valve that is easily deformed at the time of suction is particularly It can be maintained stably.

  According to a third aspect of the present invention, in the second aspect of the present invention, the concave portion is formed in the tread rubber along the tire circumferential direction, and the thin portion is formed in an annular shape in the tire circumferential direction. The pressing member is formed in an annular shape so as to contact the annular thin portion from the outer side in the tire radial direction on the entire circumference.

  Since the annularly formed pressing member comes into contact with the annular thin portion from the outer side in the tire radial direction, the shape of the annular thin portion can be stably maintained over the entire circumference.

  According to a fourth aspect of the present invention, in the third aspect of the present invention, the pressing member is made of an elastic material and has a diameter smaller than that of the thin-walled portion and is arranged in the dent portion in the radial direction. To do.

  A pressing member made of an elastic material and having a diameter smaller than that of the thin portion is expanded in the radial direction and disposed in the recessed portion, so that the pressing member can be brought into close contact with the thin portion, and the displacement of the pressing member is suppressed. it can.

  In invention of Claim 5, in the invention of any one of Claims 1-4, the height of the radial direction of the said pressing member is made equal to the depth of the said recessed part.

  Since the height of the pressing member in the tire radial direction is made equal to the depth of the recessed portion, the deformation of the thin portion can be more reliably suppressed.

  According to a sixth aspect of the invention, there is provided a temporary assembly in which the tread rubber and at least the tread rubber side of the tire frame member are covered with a covering member in the first aspect of the invention. When the tire is constructed, unvulcanized rubber is disposed between the outer peripheral surface of the tire frame member and the tread rubber.

  Since the unvulcanized rubber is disposed between the outer peripheral surface of the tire frame member and the tread rubber, the tread rubber can be bonded to the tire frame member by vulcanizing the unvulcanized rubber. Further, after vulcanizing the unvulcanized rubber, it can be made to act as a cushion rubber.

  In the invention according to claim 7, in the invention according to claim 6, an uneven portion is provided in advance on the outer peripheral surface of the tire frame member, and the unvulcanized rubber is fitted with the uneven portion after vulcanization. To fit.

  When the tread rubber is bonded to the tire frame member by vulcanization, the unvulcanized rubber fits into the concavo-convex portion of the outer peripheral surface of the tire frame member, so that the mechanical connection between the tread rubber and the tire frame member is ensured. It is possible to improve the bonding strength between the tread rubber and the tire frame member.

  In invention of Claim 8, in the invention of any one of Claims 1-7, when heating in the said container, the inside of a container is pressurized.

  When vulcanizing in the container, not only the inside of the container is heated, but also the pressure is further increased, so that the tread rubber is strongly pressed from the tire frame member side. For this reason, the adhesiveness of the tread rubber to the tire frame member can be further increased.

  In the invention according to claim 9, in the invention according to any one of claims 1 to 8, the tire frame member is molded using a resin material.

  That is, the material constituting the tire frame member of the present invention may be rubber (vulcanized rubber), but particularly by using a resin (excluding vulcanized rubber), the weight of the manufactured tire can be reduced. You can plan. In addition, resin is often easier to mold than rubber (vulcanized rubber), and energy required for production can be reduced.

  According to a tenth aspect of the present invention, in the ninth aspect, a thermoplastic resin material is used as the resin material.

  That is, as the resin constituting the tire frame member, for example, a thermosetting resin or the like can be used, but in particular, the reuse (recycling) is facilitated by using the thermoplastic resin.

  Further, as the resin constituting the tire frame member, it is desirable to use a thermoplastic elastomer (TPE) or the like in consideration of the elasticity at the time of travel and the moldability at the time of manufacture in addition to the above ease of reuse.

  In the invention (tire) according to the eleventh aspect, the tire frame member is vulcanized or semi-cured on the outer side in the tire radial direction of the tire frame member, and a thin portion is formed by a dent part partially configured on the outer side in the tire radial direction. A tread rubber having a thinned portion is disposed, and the tread rubber and at least the tread rubber side of the tire frame member are covered with a covering member to form a temporary assembly, and the inside of the covering member is sucked through the valve to tread the tread rubber. A tire in which the tread rubber is bonded to the tire frame member by pressing the rubber toward the tire frame member, housing the temporary assembly in a container, and heating the container, the recess The inside of the covering member is sucked in a state in which a pressing member that presses the thin portion from the outer side in the tire radial direction toward the tire frame member is disposed on at least a part of the portion. It is pressed against the tread rubber to the tire skeleton member Te.

  This tire can be provided at a low cost without using a vulcanization mold that requires a large vulcanizer. In addition, when sucking the inside of the covering member, a pressing member that supports the thin portion from the outside in the tire radial direction is disposed in at least a part of the recessed portion of the tread rubber, and the thin portion is supported from the outside in the tire radial direction. Therefore, the tire is prevented from being deformed at the time of suction, that is, the tire in which the shape of the tread rubber is stably maintained.

  In the invention of claim 12, in the invention of claim 11, unvulcanized rubber is disposed between the outer peripheral surface of the tire frame member and the tread rubber.

  By vulcanizing the unvulcanized rubber, a tire in which the tread rubber is bonded to the tire frame member is obtained.

  In invention of Claim 13, in the invention of Claim 12, the said outer peripheral surface of the said tire frame member is previously provided with the uneven | corrugated | grooved part, and the said uneven | corrugated | grooved part after the said unvulcanized rubber is vulcanized | cured It fits.

  Even after vulcanizing the unvulcanized rubber, the irregularities provided on the outer peripheral surface of the tire frame member fit into the rubber after vulcanization, ensuring a mechanical connection between the tread rubber and the tire frame member. Therefore, the bonding strength between the tread rubber and the tire frame member is high.

  In invention of Claim 14, in the invention of any one of Claims 11-13, the said tire frame member is shape | molded with the resin material.

  That is, the material constituting the tire frame member of the present invention may be rubber (vulcanized rubber), but particularly by using resin (excluding vulcanized rubber), the weight of the tire can be reduced. it can. In addition, resin is often easier to mold than rubber (vulcanized rubber), and energy required for production can be reduced.

  The invention according to claim 15 is the invention according to claim 14, wherein the resin material is a thermoplastic resin material.

  That is, as the resin constituting the tire frame member, for example, a thermosetting resin or the like can be used. However, reuse (recycling) is facilitated by using a thermoplastic material in particular.

  Further, as the resin constituting the tire frame member, it is desirable to use a thermoplastic elastomer (TPE) or the like in consideration of the elasticity at the time of travel and the moldability at the time of manufacture in addition to the above ease of reuse.

  Examples of the thermoplastic elastomer used in the tire manufacturing method of the present invention and the thermoplastic elastomer constituting the tire frame member in the tire according to the present invention include, for example, amide-based thermoplastic elastomer (TPA) and ester defined in JIS K6418 Thermoplastic elastomer (TPC), olefin thermoplastic elastomer (TPO), styrene thermoplastic elastomer (TPS), urethane thermoplastic elastomer (TPU), crosslinked thermoplastic rubber (TPV), or other thermoplastic elastomer (TPZ) etc. are mentioned.

  Examples of the thermoplastic resin include urethane resin, olefin resin, vinyl chloride resin, polyamide resin, and the like.

  In addition, vulcanized means that the vulcanization degree required for the final product has been reached, and the semi-vulcanized state has a higher vulcanization degree than the unvulcanized state, but is required for the final product. This means that the degree of vulcanization is not reached.

  As described above, according to the tire manufacturing method and the tire according to the present invention, it is possible to reduce the manufacturing cost of the tire using the thermoplastic material for the tire frame member, and to stabilize the shape of the tread rubber. It is possible to obtain an excellent effect that it can be maintained.

FIG. 3 is an exploded cross-sectional view showing a resin tire frame member, an adhesive, a cushion rubber, a rubber cement composition, and a tread rubber. It is an expansion perspective view showing the uneven part formed in the peripheral surface of a resin-made tire frame member in a tire axial direction section. The concavo-convex portion shown in (A) is composed of an inverted trapezoidal convex portion and a trapezoidal concave portion. The concavo-convex portion shown in (B) is composed of a convex portion having a constant width dimension and a trapezoidal concave portion. The concavo-convex part shown in (C) consists of a concave part having an arcuate cross section and a convex part located between adjacent concave parts. The concavo-convex portion shown in (D) consists of convex portions arranged in a staggered manner and concave portions that are regions other than the convex portions. It is a perspective view which shows the process of winding belt-shaped tread rubber around the outer periphery of the cushion rubber arrange | positioned on the outer peripheral surface of a tire frame member. In FIG. 3, it is a perspective view which shows the state which faced | matched the edge parts of the strip | belt-shaped tread rubber wound around the outer periphery of cushion rubber, and was made into the annular | circular shape. (A) It is a 5A-5A arrow expanded sectional view in Drawing 4 showing the example where the end face along the tire radial direction has countered the tire peripheral direction in the joint of tread rubber. (B) It is 5B-5B arrow expanded sectional view which shows the example in which the end surface inclined with respect to the tire radial direction is facing substantially parallel in the joint of a tread rubber. It is a perspective view which shows the state which is expanding the diameter of the annular tread rubber with a jig | tool. It is a perspective view which shows the state which has arrange | positioned the tire frame member to the inner peripheral side of the tread rubber expanded in diameter. It is a perspective view showing the state where tread rubber is arranged on the tire diameter direction outside of cushion rubber. A vulcanized rubber layer is provided on at least a part of the outer peripheral surface of the resin tire skeleton member to which the tread rubber is bonded, and the cushion rubber is provided at least between the tread rubber and the rubber layer. It is sectional drawing which shows the example to arrange | position. FIG. 3 is a perspective view showing a temporary assembly in which cushion rubber and at least a tread rubber side of a tire frame member are covered with an envelope. It is a disassembled perspective view which shows the state which arrange | positions a pressing member on the tread rubber side of a tire frame member. FIG. 11 is an exploded perspective view showing a state in which a pressing member having a shape different from that of FIG. 10-2 is arranged on the tread rubber side of the tire frame member. It is sectional drawing which shows an example of a temporary assembly. It is sectional drawing which shows another example of a temporary assembly. It is sectional drawing which shows another example of a temporary assembly. It is sectional drawing which shows typically the example which supported the temporary assembly with the supporting member in the container for vulcanization | cure. It is sectional drawing which shows typically the example which has arrange | positioned the temporary assembly supported by the supporting member on a trolley | bogie in the container for vulcanization | cure with the said trolley | bogie. It is sectional drawing which shows the tire with which the tread rubber was adhere | attached on the tire frame | skeleton member using a thermoplastic material. It is sectional drawing which shows the tire which used the tube body of 3 rows as a tire frame member. It is sectional drawing which shows a tube body. It is sectional drawing which shows the tire which used the single row tube body as a tire frame member. It is an exploded sectional view showing a rubber tire frame member, an adhesive, a cushion rubber, a rubber cement composition, and a tread rubber. 1 is a cross-sectional view showing a tire in which a tread rubber is bonded to a rubber tire frame member.

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings. 1 to 16, in the tire manufacturing method according to the present embodiment, a tire frame member 12 is formed using a resin material in the present embodiment, and an unvulcanized surface is formed on the outer peripheral surface 12A of the tire frame member 12. A cushion rubber 14, which is an example of rubber, is disposed, and a vulcanized or semi-vulcanized tread rubber 16 is disposed outside the cushion rubber 14 in the tire diameter direction. The tread rubber 16, the cushion rubber 14, and at least the tread rubber 16 side of the tire skeleton member 12 are made to press the tread rubber 16 against the tire skeleton member 12, and the envelope 18 is an example of the covering member of the present invention. The temporary assembly 20 is configured by covering with (see FIG. 10A). Further, the temporary assembly 20 is accommodated in a container 22 (see FIGS. 14 and 15), and the container 22 is vulcanized by heating and pressurizing, for example, so that the tread rubber 16 is tired. It adheres to the skeleton member 12. As will be described later, a thermoplastic resin or a thermosetting resin can be used as the resin constituting the tire frame member 12. Furthermore, the material constituting the tire frame member 12 is not limited to resin, and may be vulcanized rubber, for example.

(Tire frame member)

  The tire frame member 12 is made of a thermoplastic material, for example, a shape corresponding to the crown portion 24 of the tire 10 and a shape corresponding to the side portion 26 connected to the inner side in the tire radial direction from both sides in the tire axial direction of the crown portion 24. And a shape corresponding to the bead portion 28 connected to the inner side in the tire radial direction of the side portion 26. A bead core 30 is embedded in the bead portion 28. As the material of the bead core 30, for example, metal, organic fiber, organic fiber coated with resin, or hard resin is used. The bead core 30 may be omitted if the rigidity of the bead portion 28 is ensured and there is no problem in fitting with the rim (not shown).

  As the resin material constituting the tire frame member 12, rubber-like elastic thermoplastic resin, thermoplastic elastomer (TPE), thermosetting resin, or the like can be used. Considering the properties, it is desirable to use a thermoplastic elastomer.

  Examples of the thermoplastic elastomer include an amide thermoplastic elastomer (TPA), an ester thermoplastic elastomer (TPC), an olefin thermoplastic elastomer (TPO), a styrene thermoplastic elastomer (TPS) defined in JIS K6418, Examples thereof include urethane-based thermoplastic elastomer (TPU), crosslinked thermoplastic rubber (TPV), and other thermoplastic elastomers (TPZ).

  Examples of the thermoplastic resin include urethane resin, olefin resin, vinyl chloride resin, polyamide resin, and the like.

  Furthermore, 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 higher, the tensile yield strength specified by JIS K7113 is 10 MPa or higher, Similarly, the tensile yield point elongation specified in JIS K7113 is 10% or more, the tensile fracture elongation specified in JIS K7113 is 50% or more, and the Vicat softening temperature (Method A) specified in JIS K7206 is 130 ° C or more. Things can be used.

  The tire frame member 12 is first molded into a half-shaped shape centered on, for example, the tire width direction center of the tire 10, that is, the tire equator plane CL, or the vicinity thereof, and the ends of the crown portion 24 are joined to each other. It is constituted by doing. For this joining, for example, a welding method using the same or different thermoplastic material or molten resin, or a hot plate is sandwiched between the ends, and the hot plates are removed while pressing the ends closer together. Then, joining may be performed by a hot plate welding method for welding a half-shaped product in a molten state at the end portion. Furthermore, a joint member 34 such as an adhesive may be used in combination with these.

  A reinforcing cord 32 is wound around the crown portion 24 in, for example, a spiral shape. As the cord 32, for example, a steel cord, a monofilament (single wire) such as a metal fiber or an organic fiber, or a multifilament (twisted wire) obtained by twisting these fibers may be used. When a steel cord is used as the cord 32, for example, a sheet (not shown) made of a thermoplastic material is attached to the outer side of the crown portion 24 in the tire diameter direction, and the cord 32 is heated while the cord 32 is heated. It can be buried by spiral winding in the circumferential direction. At this time, both the cord 32 and the sheet may be heated.

  As described above, the reinforcing cord 32 is spirally wound around the crown portion 24 in the tire circumferential direction, whereby the rigidity of the crown portion 24 in the tire circumferential direction is improved and the fracture resistance of the crown portion 24 is improved. Can be improved. In addition, this can improve the puncture resistance in the crown portion 24 of the tire 10. When reinforcing the crown portion 24, it is preferable to wind the cord 32 spirally in the tire circumferential direction because it is easy to manufacture, but the cord 32 may be discontinuous in the tire width direction. Further, the tire skeleton member 12 (for example, the bead portion 28, the side portion 26, the crown portion 24, etc.) is provided with a further reinforcing material (polymer material, metal fiber, cord, non-woven fabric, woven fabric) embedded therein. The skeleton member 12 may be reinforced.

  A seal layer 36 is provided in a portion of the bead portion 28 of the tire frame member 12 that is fitted to a rim (not shown). Thereby, the rim fit property of the bead part 28 can be improved. As the seal layer 36, rubber, resin, elastomer, or the like having a higher sealing performance than the thermoplastic material used for the tire frame member 12 can be used. Note that the seal layer 36 may be omitted if only the thermoplastic material used for the tire frame member 12 can secure the sealing performance with the rim.

  As shown in FIGS. 2A to 2D, the outer peripheral surface 12A of the tire frame member 12 is provided with an uneven portion 38 in advance, for example, and the cushion rubber 14 (FIG. 1) has these uneven portions after vulcanization. It is preferable to fit the portion 38. The uneven portion 38 can be easily formed by a mold. Since the cushion rubber 14 is easy to flow due to a decrease in viscosity due to heating, the cushion rubber 14 can be joined to the uneven portion 38 without a gap.

  The concavo-convex portions 38 shown in FIG. 2 (A) are formed by alternately forming ridge-shaped convex portions 38A and concave portions 38B extending in the tire circumferential direction on the outer peripheral surface 12A of the tire frame member 12 in the tire width direction. Is. In the cross section in the tire axial direction, the convex portion 38A is set to an inverted trapezoid whose width dimension increases from the tire center side toward the outer side in the tire radial direction. Accordingly, the recess 38B is set such that the width dimension decreases from the tire center side toward the outer side in the tire radial direction. By providing such an uneven portion 38, the cushion rubber 14 (FIG. 1) fits firmly with the uneven portion 38 after vulcanization, and a so-called anchor effect is obtained.

  2B, ridge-line-shaped convex portions 38A and concave portions 38B extending along the tire circumferential direction are alternately formed on the outer peripheral surface 12A of the tire frame member 12 in the tire width direction. In the tire axial cross section, the width dimension of the convex portion 38A and the concave portion 38B is constant in the tire radial direction.

  The uneven portion 38 shown in FIG. 2C is formed with a plurality of concave portions 38B each having a circular arc cross section extending along the tire circumferential direction on the outer peripheral surface 12A of the tire frame member 12 at predetermined intervals in the tire width direction. Is. In this example, a region located between adjacent recesses 38B is relatively a protrusion 38A.

  The uneven portion 38 shown in FIG. 2 (D) has a plurality of columnar or inverted frustoconical convex portions 38A standing on the outer side in the tire radial direction on the outer peripheral surface 12A of the tire frame member 12, and the convex portions 38A. For example, a staggered arrangement is used. In this example, a region other than the convex portion 38A is a relatively concave portion 38B.

(Arrangement of cushion rubber and tread rubber)

  As shown in FIG. 1, when the cushion rubber 14 is disposed on the outer peripheral surface 12 </ b> A of the tire skeleton member 12, for example, one or two layers of adhesive 40 are preferably applied to the outer peripheral surface 12 </ b> A. The adhesive 40 is preferably applied in an atmosphere with a humidity of 70% or less. The adhesive 40 is not limited to a specific type, but for example, a triazine thiol-based adhesive can be used. Other examples include a chlorinated rubber adhesive, a phenol resin adhesive, an isocyanate adhesive, and a halogen. A rubberized adhesive or the like can also be used.

  In addition, before applying the adhesive 40 to the outer peripheral surface 12A, it is preferable to buff the outer peripheral surface 12A with sandpaper, a grinder, or the like. This is because the adhesive 40 is easily attached to the outer peripheral surface 12A. Furthermore, it is preferable to degrease the outer peripheral surface 12A after buffing with alcohol or the like. Further, it is preferable to perform corona treatment or ultraviolet irradiation treatment on the outer peripheral surface 12A after buffing.

  When the vulcanized or semi-vulcanized tread rubber 16 is disposed on the outer side in the tire diameter direction of the cushion rubber 14, a member having adhesiveness on the back surface side of the tread rubber 16 or the outer peripheral surface side of the cushion rubber 14. For example, it is preferable to apply the rubber cement composition 42 in advance. Thereby, when the tread rubber 16 is stuck to the cushion rubber 14, a temporary fixing state is obtained, and workability is improved.

  When SBR (styrene-butadiene rubber) is used as the material of the tread rubber 16, it is preferable to use, for example, SBR-based splice cement as the rubber cement composition 42. Further, when an SBR rubber having a high NR (natural rubber) blending ratio is used as a material of the tread rubber 16, it is preferable to use a blend of BR (butadiene rubber) with an SBR splice cement. In addition, as the rubber cement composition 42, it is possible to use a solventless cement containing a liquid elastomer such as liquid BR or a cement mainly composed of a blend of IR (isoprene rubber) -SBR.

  The tread rubber 16 is PCT (Pre-Cured Trade) in which a tread pattern such as a main groove is formed in advance on the tread surface 16A side. In order to form a tread pattern, unvulcanized rubber is vulcanized in a mold for PCT, and the tread rubber 16 is molded. At this time, the tread rubber 16 has a vulcanization degree higher than a vulcanized state or an unvulcanized state that has reached a vulcanization degree required as a final product. The semi-vulcanized state is not reached. In particular, the tread rubber 16 according to the present embodiment has one or a plurality of annular recess portions 16B extending along the tire circumferential direction as shown in FIG. The portion where the recess 16B is formed is a thin portion 16C, and the portion where the recess 16B is not formed is a thick portion 16D which is thicker than the thin portion 16C. (See FIG. 1 etc.). Particularly in the present embodiment, the recessed portion 16 </ b> B is formed in an annular shape along the tire circumferential direction and serves as a main groove of the tire 10. The thickness of the thin portion 16C and the thick portion 16D is not particularly limited as long as the performance required for the tire is satisfied. For example, the thickness T1 of the thin portion 16C is about 1 mm, the tire center portion (the thickest portion). The wall thickness T2 of the thick wall portion 16D is about 5 mm.

  When the tread rubber 16 is disposed on the outer periphery of the cushion rubber 14, as shown in FIGS. 3 to 5, the belt-like tread rubber 16 may be wound around the outer periphery of the cushion rubber 14 in an annular shape. As shown in FIGS. 6 to 8, a tread rubber 16 formed in an annular shape in advance may be used.

  Here, in FIG. 3 to FIG. 5, a method for winding the belt-like tread rubber 16 around the outer diameter of the cushion rubber 14 in an annular shape will be briefly described. In this method, as shown in FIG. 3, the tire frame member 12 in which the cushion rubber 14 is disposed on the outer peripheral surface 12 </ b> A is supported by, for example, a disk-shaped support member 44, and the support provided at the center of the support member 44. The tire frame member 12 is rotated in the direction of arrow A around the shaft 46, and the tread rubber 16 supplied from the direction orthogonal to the tire axis direction is cushion rubber 14 (see FIG. 5) disposed on the outer peripheral surface 12A of the tire frame member 12. 1) is wound around the outer circumference and cut. And as FIG. 4 shows, edge parts are faced | matched and it is set as an annular | circular shape. 5 (A) and 5 (B), for example, an unvulcanized rubber 50 is disposed at the joint 48 between the end portions, and the end portions are vulcanized and bonded in a vulcanization step described later. As shown in FIG. 5 (A), the cross-sectional shape of the seam 48 may be a simple butt where the end surfaces along the tire radial direction are opposed to the tire circumferential direction, and as shown in FIG. 5 (B), The end face inclined with respect to the tire radial direction may be a butt facing each other substantially in parallel.

  Next, a method for arranging the annular tread rubber 16 on the outer side in the tire diameter direction of the cushion rubber 14 in FIGS. 6 to 8 will be briefly described. In this method, as shown in FIG. 6, the annular tread rubber 16 is expanded in diameter by a jig 52, and the tire frame member 12 is disposed on the inner peripheral side of the expanded tread rubber 16. Although not shown, a cushion rubber 14 (see FIG. 1) is disposed on the outer peripheral surface 12A of the tire frame member 12.

  The jig 52 includes a plurality of (in the present embodiment, a total of eight) moving blocks 56 arranged in a circle on the upper surface of a disk-shaped pedestal 54. These moving blocks 56 are configured to be movable in synchronism with the diametrically inner side (arrow E direction) and the diametrically outer side (arrow F direction) of the pedestal 54 by a feeding means (not shown) such as a cylinder or a screw. . Each moving block 56 is provided with a plurality of pins 58 (two in total in the present embodiment). A plurality of pins 60 are arranged along a circle on the inner peripheral side of the pins 58 in the pedestal 54.

  Note that all the pins 58 are arranged at positions along a circle, and are moved to the inside in the diameter direction (arrow E direction) and the outside in the diameter direction (arrow F direction) of the base 54 by the movement of each moving block 56. It is like that.

  Therefore, the annular tread rubber 16 is disposed on the outer peripheral side of each pin 58, and the diameter of the tread rubber 16 is increased by moving each moving block 56 to the outside of the pedestal 54 in the diameter direction (arrow F direction). Thereafter, as shown in FIG. 7, the tire frame member 12 is disposed on the inner peripheral side of the tread rubber 16. At this time, the tire frame member 12 is disposed between the pin 58 and the pin 60.

  Thereafter, by pulling out all the pins 58 and 60 from between the tread rubber 16 and the tire frame member 12, as shown in FIG. 8, the tread rubber 16 is in the tire radial direction of the cushion rubber 14 (not shown). It will be in the state arranged outside. At this time, the cushion rubber 14 is sandwiched between the outer peripheral surface 12 </ b> A of the tire frame member 12 and the tread rubber 16 by the tension of the annular tread rubber 16 whose diameter has been expanded.

  As shown in FIG. 9, a vulcanized rubber layer 62 </ b> A is provided on at least a portion of the outer peripheral surface 12 </ b> A of the tire frame member 12 to which the tread rubber 16 is bonded, and the cushion rubber 14. May be disposed at least between the tread rubber 16 and the rubber layer 62A. The rubber layer 62 </ b> A is, for example, an end portion on the tread side of the side rubber 62 provided on the side portion 26 of the tire frame member 12, and the side rubber 62 extends to the outer peripheral surface 12 </ b> A of the tire frame member 12. The side rubber 62 is fixed to the tire frame member 12 by adhesion, for example.

  When the tire frame member 12 is a tube body, the belt-shaped tread rubber 16 may be wound in a spiral shape continuously in the tire circumferential direction with an internal pressure applied to the tube body. In the case of the tire frame member 12 with beads, the tread rubber 16 may be disposed in a state where the tire frame member 12 is assembled with a rim and an internal pressure is applied through a valve (not shown) provided on the rim. .

(Assembly and vulcanization of temporary assembly)

  Next, as shown in FIGS. 10A to 13, a temporary assembly 20 is configured by covering the tread rubber 16, the cushion rubber 14, and at least the tread rubber 16 side of the tire frame member 12 with an envelope 18. . The envelope 18 is a covering member made of, for example, rubber having airtightness and stretchability, moderately stable thermally and chemically, and having appropriate strength. The envelope 18 is provided with a valve 64 for evacuating the area covered with the envelope 18 to press the tread rubber 16 against the tire frame member 12 side. The valve 64 preferably has a valve mechanism (not shown) for preventing the inflow of air from the outside into the envelope 18 after evacuation.

  As shown in detail in FIGS. 10-2 and 11, a pressing member 90 accommodated in the recessed portion 16 </ b> B is disposed between the tread rubber 16 and the envelope 18. In the example shown in FIG. 10-2, the pressing member 90 is formed in an annular shape so as to be accommodated over the entire circumference in the tire circumferential direction with respect to the recessed portion 16B. The pressing member 90 is made of an elastic material (for example, rubber having physical properties that can withstand the pressure and temperature in the envelope 18), and the width W2 of the pressing member 90 is also the inner dimension of the recessed portion 16B. The width W1 is slightly smaller. In particular, in the present embodiment, the inner diameter of the pressing member 90 in the natural state is slightly smaller than the outer diameter of the tread rubber 16 in the thin portion 16C.

  The pressing member 90 having such a shape is accommodated in the recessed portion 16 </ b> B while its inner diameter is slightly enlarged. As a result, the pressing member 90 closely contacts the thin wall portion 16C from the outer side in the tire radial direction and supports the thin wall portion 16C to be pressed toward the outer side in the radial direction, thereby suppressing deformation of the thin wall portion 16C when the inside of the envelope 18 is sucked. It has enough wall thickness so that it can.

  The height H2 of the pressing member 90 is equal to the depth D1 of the recessed portion 16B, and the tread rubber 16 tread surface 16A and the outer surface 90S of the pressing member 90 are flush with each other, so the outer surface 90S of the pressing member 90 is It is in contact with the envelope 18. When the height of the pressing member 90 is lower than the depth D1 of the recessed portion 16B, a gap is generated between the outer surface of the pressing member 90 and the envelope 18, so that when the inside of the envelope 18 is sucked, Although there is a possibility that the thin portion 16C may be lifted integrally, in the present embodiment, such lift is prevented. When the height of the pressing member 90 is higher than the depth D1 of the recessed portion 16B, the outer surface of the pressing member 90 protrudes from the tread surface 16A of the tread rubber 16, so that the tread surface 16A and the envelope 18 are near the pressing member 90. However, in this embodiment, such a gap is not generated.

  Although the cap 64M is formed in the valve 64, as described above, the pressing member 90 is formed in an annular shape and surrounds the tread rubber 16 with the thin wall portion 16C, and therefore inevitably in the vicinity of the cap 64M. Is accommodated in the recess 16B, and the thin portion 16C of this portion is pressed and supported from the outside in the radial direction. In the vicinity of the base portion 64M, the thin portion 16C is most easily deformed, but the pressing member 90 effectively suppresses this deformation.

  The inner diameter of the pressing member 90 in the natural state does not need to be smaller than the outer diameter of the thin portion 16C, but if it is smaller, the pressing member housed in the recessed portion 16B as described above. 90 tightly contacts the thin-walled portion 16C from the outside in the tire radial direction, and the pressing member 90 does not inadvertently shift or rise from the recessed portion 16B.

  Further, as shown in FIG. 10C, the pressing member 92 may be formed in an arc shape and shaped so as to be accommodated only in a part in the circumferential direction with respect to the recessed portion 16B. That is, even with the pressing member 92 having such a shape, the thin-walled portion 16 </ b> C where the pressing member 92 is in contact can suppress deformation when the inside of the envelope 18 is sucked. In addition, it is preferable to adjust the position of the pressing member 92 accommodated in the recessed portion 16B only in a part in the circumferential direction so as to be accommodated in the recessed portion 16B at least in the vicinity of the base portion 64M. . The length of the pressing member 92 is preferably at least about 10 cm because deformation of the thin portion 16C in the vicinity of the base portion 64M can be suppressed.

  In the example shown in FIGS. 10A and 11B, the tire frame member 12 is assembled to a pair of annular support members 66 having a structure close to a rim, and the bead portion 28 is attached to the flange portion 66F of the support member 66. It is in close contact. The envelope 18 covers the outer surfaces of the side portions 26 on both sides of the tire frame member 12 and the tread rubber 16, and an edge (not shown) on the inner side in the tire diameter direction is between the bead portion 28 and the flange portion 66F. It is sandwiched.

  By evacuating from the valve 64 in this state, the envelope 18 can be brought into close contact with the tread rubber 16 and the tire frame member 12, and the tread rubber 16 can be pressed against the tire frame member 12 side. A predetermined gap 68 is provided between the pair of support members 66. By applying pressure during vulcanization to the inner surface side of the tire frame member 12 through the gap 68 (in the direction of arrow C), the shape of the tire frame member 12 can be maintained.

  Further, as shown in FIG. 12, a bladder 70 may be disposed on the inner surface side of the tire frame member 12. The configuration of the envelope 18 is the same as in FIG. In this example, by inflating the bladder 70 during vulcanization, pressure can be applied to the inner surface side of the tire frame member 12 to maintain the shape of the tire frame member 12.

  Further, as shown in FIG. 13, when the tire frame member 12 has sufficient rigidity so as not to be deformed when the envelope 18 is evacuated, the tread rubber 16 is not used without using the support member 66. Further, not only the outer surface side of the tire frame member 12 but also the inner surface side may be covered with the envelope 18.

  In addition, by using a jig (not shown) in which a plurality of inner pieces movable in the tire radial direction are arranged in the tire circumferential direction, each inner piece is moved outward in the tire radial direction, whereby the crown of the tire frame member 12 is obtained. The shape of the crown portion 24 may be maintained by supporting the portion 24 from the inner surface side. This jig is preferably easy to disassemble and assemble.

  Then, as shown in FIGS. 14 and 15, the temporary assembly 20 is accommodated in a container 22, and vulcanization is performed by heating and pressurizing the container 22. The container 22 is a so-called vulcanization can, but may be any container as long as it has a capacity for accommodating the temporary assembly 20 and can withstand heating and pressurization during vulcanization. The vulcanization conditions are, for example, a temperature of 120 ° C., a pressure of 2026 hPa (2 atm), and a time of 1 hour.

  From the viewpoint of preventing deformation of the tread rubber 16 and the like, when the temporary assembly 20 is stored in the container 22, it is desirable that the outer peripheral portion of the temporary assembly 20 does not contact the inner wall or the like of the container 22. As means for that, for example, as shown in FIG. 14, a system in which one or a plurality of temporary assemblies 20 are supported by a support member 72, or as shown in FIG. 15, a single or a plurality of temporary assemblies 20. Is supported by a support member 74 provided on the carriage 76, and the temporary assembly 20 is arranged in the container 22 together with the carriage 76.

  Here, sulfur or peroxide can be used as the vulcanization accelerator. Carbon black or silica can be used as the reinforcing agent for the cushion rubber 14, and silica is more preferable. Further, aminosilane or polysulfide can be used as the coupling agent.

  The vulcanization temperature is preferably 100 ° C or higher and lower than 160 ° C. If the temperature is 160 ° C. or higher, the crown portion 24 (see FIGS. 11 to 13) reinforced by the cord 32 may buckle due to thermal contraction of the thermoplastic material used for the tire frame member 12. is there. Moreover, it is because the vulcanization degree of the cushion rubber 14 may become inadequate that it is less than 100 degreeC.

  Thus, the cushion rubber 14 is vulcanized by setting the temperature in the container 22 and setting the pressure in the container 22 to a pressure suitable for vulcanization and performing vulcanization for a predetermined time. Thereby, as shown in FIG. 16, the tread rubber 16 and the outer peripheral surface 12A of the tire frame member 12 are vulcanized and bonded to form the tire 10 (pneumatic tire). When the semi-vulcanized tread rubber 16 is used, the tread rubber 16 is further vulcanized to reach the vulcanization degree of the final product. As shown in FIGS. 5A and 5B, when the belt-shaped tread rubber 16 is used and the unvulcanized rubber 50 is disposed at the joint 48, the unvulcanized rubber 50 is added. The seam 48 of the tread rubber 16 is also vulcanized and bonded.

  Thus, in this embodiment, the tire 10 is manufactured by bonding the tread rubber 16 to the tire frame member 12 using a thermoplastic material without using a vulcanization mold that requires a large vulcanizing device. be able to. For this reason, the manufacturing cost of the tire 10 using the thermoplastic material for the tire frame member 12 can be reduced.

  In addition, since the pressing member 90 is accommodated in the recess 16B between the tread rubber 16 and the envelope 18 when the inside of the envelope 18 is sucked, the deformation of the thin portion 16C caused by the suction in the envelope 18 Can be suppressed. That is, when manufacturing the tire 10, the shape of the tread rubber 16 can be stably maintained.

  In the present invention, the target portion for suppressing deformation when the inside of the envelope 18 is sucked is not limited to the thin portion 16 </ b> C constituting the main groove of the tire 10. For example, even if it is other than the thin portion 16C constituting the main groove, the pressing member 90 may be disposed and sucked to the thin portion that may be deformed when sucked in the envelope 18.

  The pressurization in the container 22 is not necessarily essential, and vulcanization can be performed only by heating. However, the pressure inside the container 22 can increase the adhesion of the tread rubber 16 to the tire frame member 12.

  As shown in FIG. 9, when the cushion rubber 14 is disposed between the tread rubber 16 and the vulcanized rubber layer 62A provided on the outer peripheral surface 12A of the tire frame member 12, the vulcanization is performed. Since the vulcanized rubber or semi-vulcanized rubber (tread rubber 16) and the vulcanized rubber (rubber layer 62A) can be vulcanized and bonded, the tread rubber 16 can be easily attached to the tire frame member 12 using a thermoplastic material. Can be glued to. When the vulcanized rubber layer 62A is a part of the side rubber 62, the number of steps can be reduced and the manufacturing cost of the tire 10 can be further reduced as compared with the case where the side rubber 62 is separately provided.

  Not only between the vulcanized rubber layer 62A and the tread rubber 16, but also between the tread rubber 16 and the region of the outer peripheral surface 12A of the tire frame member 12 where the rubber layer 62A is not provided. A cushion rubber 14 may be provided.

  As shown in FIGS. 2A to 2D, when the uneven portion 38 is provided on the outer peripheral surface 12 </ b> A of the tire frame member 12, the uneven portion 38 is fitted with the cushion rubber 14 after vulcanization. Since the mechanical coupling between the tread rubber 16 and the tire frame member 12 is ensured, the bonding strength between the tread rubber 16 and the tire frame member 12 in the tire 10 is increased.

  The form in which the tread rubber 16, the cushion rubber 14, and at least the tread rubber 16 side of the tire frame member 12 are covered with the envelope 18 is not limited to the present embodiment and the illustrated configuration. The order of the steps in the tire manufacturing method according to the present embodiment can be changed as appropriate.

  Furthermore, although the tire 10 according to the above embodiment is a tubeless type tire using the tire frame member 12 with the bead core 30, the configuration of the tire 10 is not limited to this. As shown in FIG. 17, a hollow tube body 78 formed in an annular shape in the tire circumferential direction and disposed on the outer peripheral portion of the rim 80 may be used as the tire frame member 12 using a thermoplastic material. The tube bodies 78 can be arranged in a double row (FIG. 17) or a single row (FIG. 19) in the tire width direction.

  In the example shown in FIG. 17, three tube bodies 78 are arranged on the outer peripheral portion of the rim 80 as the tire frame member 12. For example, a tread rubber 16 in which a reinforcing belt layer 82 is embedded is disposed across the outer periphery of these tube bodies 78 via, for example, a cushion rubber 14 and vulcanized and bonded.

  As shown in FIG. 18, the tube body 78 is formed by welding the tube half bodies 78A having a semicircular cross section facing each other with a welding thermoplastic material 86, or by joining with a welding sheet (not shown). be able to.

  In the example shown in FIG. 19, as the tire frame member 12, one tube body 78 including two tube halves 78 </ b> A is disposed on the outer peripheral portion of the rim 80. On the outer peripheral portion of the tube body 78, for example, a tread rubber 16 in which a reinforcing belt layer 82 is embedded is disposed, for example, via a cushion rubber 14, and is vulcanized and bonded.

  In any of the tires 10 shown in FIGS. 17 and 19, the tire manufacturing method described above can be used as a method of adhering the tread rubber 16 to the outer peripheral portion of the tube body 78.

  In the present invention, the tire frame member is not limited to the thermoplastic material described above. That is, if a resin material (including a thermosetting material) is used, it is possible to reduce the weight, and the tire frame member can be easily molded, and less energy is required for manufacturing the tire. Cost can also be reduced. In particular, if a thermoplastic material is used for the tire frame member, the tire frame member can be easily reused (recycled).

  On the other hand, the tire frame member may be made of rubber. In this case, as shown in FIG. 20, a so-called base tire 102 in a state where the tread is removed from the used rubber tire can be used as the tire frame member according to the present invention. The base tire 102 includes a carcass ply 106 disposed between the bead cores 104 and a cord 108 disposed on the radially outer side of the carcass ply 106 as necessary.

  Then, the tread rubber 16 is disposed and bonded to the outer peripheral surface (crown portion) of the base tire 102. In this step, the pressing member 90 or the pressing member 92 is similar to the steps shown in FIGS. However, evacuation is performed from the valve 64 while being accommodated in the recess 16B. The obtained tire 100 becomes a retread tire in which deformation of the tread rubber 16 is suppressed as shown in FIG. Of course, the present invention can be applied not only to retreaded tires but also to manufacturing unused tires (new tires) in which the tire frame member is made of rubber.

  In particular, in a tire for a passenger car, a recess 16B such as a circumferential groove or a width direction groove is formed in the tread rubber 16 as compared with a tire used for a bus or truck, a tire used for an aircraft, or the like. In many cases, the structure has the thin portion 16C. That is, the present invention can be particularly preferably applied when manufacturing or rehabilitating such a passenger car tire.

DESCRIPTION OF SYMBOLS 10 Tire 12 Tire frame member 12A Outer peripheral surface 14 Cushion rubber (unvulcanized rubber)
16 Tread rubber 18 Envelope 20 Temporary assembly 22 Container 38 Concavity and convexity 62 Side rubber 62A Rubber layer 90 Pressing member 92 Pressing member 100 Tire 102 Stand tire (tire frame member)

Claims (15)

A tread rubber having a thinned portion that is made vulcanized or semi-cured on the outer side in the tire radial direction of the tire skeleton member and partially thinned by a recessed portion configured on the outer side in the tire radial direction,
The tread rubber and at least the tread rubber side of the tire frame member are covered with a covering member to form a temporary assembly, and the inside of the covering member is sucked through the valve to press the tread rubber toward the tire frame member.
A method for manufacturing a tire for adhering the tread rubber to the tire frame member by housing the temporary assembly in a container and heating the container,
The tire manufacturing method which arrange | positions the pressing member which can press the said thin part toward the said tire frame | skeleton member from the tire radial direction outer side to at least one part of the said recessed part, and attracts | sucks the inside of a covering member.   2. The tire manufacturing method according to claim 1, wherein the pressing member is disposed in the recess at least at a position radially inward of the valve with respect to the valve. The concave portion is formed in the tread rubber along the tire circumferential direction, and the thin portion is an annular thin portion formed annularly in the tire circumferential direction,
The tire manufacturing method according to claim 2, wherein the pressing member is formed in an annular shape so as to contact the annular thin portion from the outer side in the tire radial direction on the entire circumference.   The tire manufacturing method according to claim 3, wherein the pressing member is made of an elastic material and has a diameter smaller than that of the thin-walled portion, and is arranged in the recessed portion in a radial direction.   The tire manufacturing method according to any one of claims 1 to 4, wherein a height of the pressing member in a radial direction is made equal to a depth of the recessed portion.   An unvulcanized rubber is disposed between the outer peripheral surface of the tire frame member and the tread rubber when the tread rubber and at least the tread rubber side of the tire frame member are covered with a covering member to form a temporary assembly. The tire manufacturing method according to any one of claims 1 to 5.   The tire manufacturing method according to claim 6, wherein an uneven portion is provided in advance on the outer peripheral surface of the tire frame member so that the unvulcanized rubber is fitted to the uneven portion after vulcanization.   The tire manufacturing method according to any one of claims 1 to 7, wherein the interior of the container is pressurized when heating is performed in the container.   The tire manufacturing method according to any one of claims 1 to 8, wherein the tire frame member is formed using a resin material.   The tire manufacturing method according to claim 9, wherein a thermoplastic resin material is used as the resin material. A tread rubber having a thinned portion that is made vulcanized or semi-cured on the outer side in the tire radial direction of the tire skeleton member and partially thinned by a recessed portion configured on the outer side in the tire radial direction,
The tread rubber and at least the tread rubber side of the tire frame member are covered with a covering member to form a temporary assembly, and the inside of the covering member is sucked through the valve to press the tread rubber toward the tire frame member.
The temporary assembly is contained in a container, and by heating the container, the tread rubber is a tire bonded to the tire frame member,
The inside of the covering member is sucked and the tread rubber is directed toward the tire frame member in a state in which a pressing member that presses the thin wall portion from the outer side in the tire radial direction toward the tire frame member is disposed in at least a part of the recess. The tire being pressed.   The tire according to claim 11, wherein unvulcanized rubber is disposed between an outer peripheral surface of the tire frame member and the tread rubber. The outer peripheral surface of the tire frame member is provided with an uneven portion in advance,
The tire according to claim 12, wherein the unvulcanized rubber is fitted to the uneven portion after vulcanization.   The tire according to any one of claims 11 to 13, wherein the tire frame member is formed of a resin material.   The tire according to claim 14, wherein the resin material is a thermoplastic resin material.

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