JP4474263B2 - Tire manufacturing method and green tire molding apparatus - Google Patents

Description

  The present invention relates to a tire manufacturing method and a green tire molding apparatus, and more particularly to a tire manufacturing method and a green tire that can maintain a tire shape at the time of green tire molding until vulcanization using a molding and vulcanizing bladder. The present invention relates to a tire forming apparatus.

  When molding a radial tire, bead wires are attached to both ends of a body ply formed in a cylindrical shape, and the bead portions of the body ply are respectively supported by a pair of movable bodies that can approach each other. Further, a bladder made of an elastic material such as rubber is attached between both moving bodies, and a body ply is disposed on the outer peripheral side of the bladder. Then, pressurized air is supplied to the inside of the bladder to bring the bladder into close contact with the inner peripheral surface of the body ply, and the body ply is expanded by both moving bodies while the axially intermediate portion of the body ply bulges and expands through the bladder. The body plies are deformed into a toroidal shape by moving the two bead portions toward each other. Next, a belt layer, a tread, a sidewall, and the like are sequentially bonded to the outer surface of the body ply formed in the toroidal shape to form a raw tire before vulcanization.

  However, it is difficult to form a bladder made of an elastic material such that the entire bladder has a uniform stretch rate, or to form the entire bladder with a uniform thickness. For this reason, the bladder is expanded and expanded in diameter. In some cases, the shape is not a predetermined toroidal shape set in advance, but a distorted shape. As a result, there has been a problem that the body ply bulged and deformed through the bladder cannot be formed into the required toroidal shape and a pre-vulcanized raw tire having a good shape cannot be obtained.

  In addition, even with a bladder that is made of an elastic material, even if a uniform bladder can be formed, it is extremely difficult to obtain a tire shape that is close to the final shape even though it is a toroidal shape. I often got tires afterwards. In this way, because the tire is greatly deformed from the raw tire, the rubber placement, strength, etc. at each position of the tire do not go according to the set target. There has been a demand for molding tires.

  As what improves it, what is described in patent document 1 is known. In the thing of this patent document 1, in order to make it bulge and expand to the predetermined toroidal shape set beforehand beforehand, in order to make the said bladder expand into a predetermined toroidal shape, several non-elongate thread form set so that it might become a predetermined toroidal shape A three-layer structure is formed by combining an aggregate made of the above and a pair of rubber layers covering the aggregate in a sandwich shape. That is, the aggregate is a lattice-like structure composed of a first thread group disposed in the circumferential direction of the bladder and a second thread group disposed in a direction intersecting the thread group, and the bulging diameter of the bladder is increased. In some cases, the lengths and the arrangement structure of the respective filaments forming the aggregate are set so as to have a predetermined toroidal shape set in advance. As a result, it is possible to obtain a raw tire before vulcanization having a raw tire shape that is almost the same as the tire shape after vulcanization that is close to the final shape as set in advance.

  However, the internal pressure of the three-layered bladder that supports this good green tire is released and the green tire is taken out and transported to the vulcanizer. Because it is necessary to obtain a tire by vulcanizing in between, the raw tire that has been molded well will be deformed no matter how carefully it is handled until the molded bladder is pulled out and the vulcanized bladder is inserted The problem was inevitable.

As described in Patent Document 2, as a material that hardly deforms from a raw tire before vulcanization to a tire after vulcanization, a hard core type that gradually builds up a tire material on a support composed of a strong core that can be disassembled. There is something. This kind of hard core type certainly produces a raw tire on the hard core, puts it in a vulcanizer as it is, and vulcanizes it, so that a good tire can be obtained without deformation after the raw tire is made.
JP-A-8-11239 (paragraphs 0016 to 0018, FIGS. 1 and 2) JP-A-63-89336

  However, in the thing of the above-mentioned patent document 2, since a hard core will be occupied from the shaping | molding process of a green tire to the completion | finish of the vulcanization process which requires more time compared with this shaping | molding process, many expensive hard cores are required. As a result, the cost was high. In addition, since a raw tire is sandwiched between the hard core and the mold and vulcanized by applying high temperature and pressure, the hard core and the tire are strongly bonded, and it takes a lot of time and labor to peel off the tire after vulcanization from the hard core. Was a problem. In addition, if the hard core is not cooled, the next tire cannot be molded, and it is necessary to heat again at the time of the next vulcanization.

  The present invention was made in order to solve the above-described conventional problems, and using a molding and vulcanizing bladder, the raw tire was molded into a shape as close as possible to the final shape, and the shape was maintained. It is an object of the present invention to provide a tire manufacturing method and a green tire molding apparatus that can be vulcanized as it is, and that can easily peel off the bladder and tire after vulcanization.

  In order to solve the above-mentioned problems, the invention described in claim 1 includes a raw tire molding stage in which an inner element and an outer element constituting a tire are assembled to form a raw tire, and a raw tire molded in the raw tire molding stage. In the tire manufacturing method including the vulcanization stage for vulcanizing the tire, the following steps (1) to (5) are sequentially performed to manufacture the tire.

(1) A state where an outer flexible membrane for both molding and vulcanization is fitted on a molding drum having an inner flexible membrane and an aggregate layer, and the inner element is fitted on the outer peripheral side of the outer flexible membrane. Then, the inner element is formed into a predetermined shape by expanding and expanding the bladder having a three-layer structure including the inner flexible membrane, the aggregate layer, and the outer flexible membrane,

(2) A green tire is formed by mounting the outer element on the outer side of the inner element formed in a predetermined shape,

(3) After forming the raw tire, the inner flexible membrane and the aggregate layer are contracted and shrunk with respect to the outer flexible membrane to separate the inner flexible membrane and the aggregate layer from the outer flexible membrane,

(4) Move in a state in which pressure is maintained in the outer flexible membrane, and then seal the heated and pressurized fluid in the outer flexible membrane, vulcanize the raw tire,

(5) After vulcanization, the outer flexible membrane is contracted and contracted to separate the outer flexible membrane from the inside of the tire after vulcanization.

  According to a second aspect of the present invention, in the first aspect, in the molding step, the raw tire is expanded and expanded in a toroidal shape with a bladder having a three-layer structure of the inner flexible membrane, the aggregate layer, and the outer flexible membrane. In the vulcanization step, the toroidal shape is maintained only by the outer flexible membrane.

  According to a third aspect of the present invention, in the first or second aspect, the aggregate layer is composed of a plurality of yarns having high tensile strength and not extending, and the yarns extend along the circumferential direction. The three-layer structure bladder is formed by a first yarn group arranged in a lattice pattern and a second yarn group arranged along the direction intersecting the first yarn group. It is characterized by being configured so as to have a preset toroidal shape when the diameter is expanded.

  According to a fourth aspect of the present invention, in any one of the first to third aspects, the outer flexible membrane is separated from the inner flexible membrane and the aggregate layer after completion of the forming step, and the inner flexible membrane is separated. Is sealed to maintain the toroidal shape, and the raw tire is conveyed to the vulcanization process in that state.

  According to a fifth aspect of the present invention, there is provided a raw tire molding apparatus for molding a raw tire by assembling an inner element and an outer element constituting a tire, and fitting the outer periphery of a molding drum having an aggregate layer and an inner flexible film. The outer flexible membrane, which is used for molding and vulcanization, and the inner flexible membrane, the aggregate layer, and the outer flexible membrane with the inner element fitted on the outer circumference of the outer flexible membrane. Means for supplying a pressurized gas into a bladder having a layer structure to bulge and expand the bladder, forming the inner element in a toroidal shape, and fitting the outer element outside the inner element of the toroidal shape; A raw tire generating means for generating a raw tire by bringing an inner element and an outer element into close contact with each other, and shrinking and reducing the diameter of the aggregate layer and the inner flexible film with respect to the outer flexible film, thereby forming the outer flexible film as an aggregate Separating means separated from the inner layer and the inner flexible membrane, and the aggregate layer and A sealing means for sealing the inside of the outer flexible membrane separated from the inner flexible membrane to maintain a toroidal shape, and a conveying means for conveying the raw tire to the vulcanization process while being sealed by the sealing means It is characterized by that.

  A sixth aspect of the present invention is characterized in that, in the fifth aspect, the outer flexible film is supported by a pair of cylindrical bodies whose both end portions can approach and separate from each other.

According to a seventh aspect of the present invention , in the sixth aspect of the present invention, in the sealing means, the inner end portions are abutted and locked to each other by the movement of the pair of cylindrical bodies of the outer flexible membrane toward each other. In addition to sealing the inside of the flexure film, the sealing film is provided with a sealing device that is unlocked by the movement of the pair of cylindrical bodies in a direction away from each other.

  According to the invention of claim 1 configured as described above, the tire shape after vulcanization is obtained by expanding and expanding the bladder having a three-layer structure including the inner flexible membrane, the aggregate layer, and the outer flexible membrane. After forming the raw tire, the inner flexible membrane and the aggregate layer are contracted and shrunk to separate the outer flexible membrane, and the pressure is maintained in the outer flexible membrane. Since the raw tire was vulcanized with the inside of the outer flexible membrane sealed and the prescribed shape maintained, the shape of the raw tire and the shape of the tire after vulcanization can be made almost the same, and the strength as initially set Can be easily obtained, and after vulcanization, the outer flexible membrane can be easily separated from the tire, eliminating the need to remove the hard core from the tire as in the case of a hard core. This improves productivity and the heat capacity of the outer flexible membrane. Since even small, there is an effect capable of performing good manufacturing process thermal efficiency.

  According to the invention according to claim 2 configured as described above, in the molding stage, the raw tire is swelled in a toroidal shape by a bladder having a three-layer structure of the inner flexible membrane, the aggregate layer, and the outer flexible membrane. In the vulcanization stage, the toroidal shape is maintained only by the outer flexible membrane, so even after the aggregate layer is removed, due to the presence of the outer flexible membrane, It is possible to vulcanize a raw tire while maintaining a good toroidal shape without being deformed before being vulcanized, and to obtain a post-vulcanized tire having a preset shape. There is an effect that can.

  According to the invention according to claim 3 configured as described above, the aggregate layer is composed of a plurality of yarns having high tensile strength and not extending, and the yarns are arranged along the circumferential direction. The first yarn group provided and the second yarn group disposed along the direction intersecting with the first yarn group are formed in a lattice shape, and the aggregate layer has the three-layer structure. Because it is configured to have a preset toroidal shape when the bladder expands and expands, the three-layered bladder can reliably shape the raw tire into the required toroidal shape, and the shape is good There is an effect that a tire before vulcanization can be obtained with certainty.

  According to the invention according to claim 4 configured as described above, after the forming step, the outer flexible membrane is separated from the inner flexible membrane and the aggregate layer, and the inside of the outer flexible membrane is sealed. Thus, the toroidal shape is maintained, and the raw tire is conveyed to the vulcanization process in that state, so that there is an effect that the toroidal shape can be easily maintained by sealing in the outer flexible film.

  According to the invention of claim 5 configured as described above, means for supplying pressurized gas into a three-layered bladder comprising an inner flexible membrane, an aggregate layer and an outer flexible membrane, and an inner element The outer element is brought into close contact with each other to produce a raw tire, the outer flexible membrane is separated from the aggregate layer and the inner flexible membrane, the outer flexible membrane is sealed, and the sealing means is sealed. Since it is composed of a conveying means that conveys the raw tire to the vulcanization process in a state where it has been made, the state can be maintained until the raw tire molded into a toroidal shape is vulcanized, without using a hard core Therefore, it is possible to reliably obtain a pre-vulcanized tire and to eliminate various problems caused by using a hard core.

  According to the invention according to claim 6 configured as described above, the outer flexible membrane is supported by a pair of cylindrical bodies whose both end portions can be approached and separated from each other. The pressurized gas supplied into the rubber film can be sealed, and the toroidal shape can be easily maintained.

According to the invention according to claim 7 configured as described above, the sealing means is configured to be capable of being externally contacted and locked due to displacement in a direction in which the pair of cylindrical bodies of the outer flexible membrane approach each other. Since the inside of the flexure film is sealed and the sealing means is released by the displacement of the pair of cylinders in the direction away from each other, the structure of the sealing seal means can be facilitated and the pair of cylinders There is an effect that can be sealed by a simple operation of only approaching and separating the body.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 shows a schematic cross-sectional view of a pneumatic tire 10, and FIG. 2 shows a state before assembly of each component constituting the tire 10. In the figure, reference numeral 11 denotes a chacher provided on both sides of the inner periphery that come into contact with the rim of the tire 10, and special rubber is blended to rub against the rim. An inner liner 12 is provided inside the tire 10, and the inner liner 12 is made of rubber with poor air permeability. A body ply 13 that forms the skeleton of the tire 10 is provided outside the inner liner 12, and bead portions 16 including a bead core 14 and an apex 15 are provided at folded portions at both ends of the body ply 13. The chacher 11, the inner liner 12, the body ply 13, and the bead portion 16 constitute an inner element 17 of the tire 10.

  A first belt 21 and a second belt 22 are wound around the outer side of the body ply 13. A cap cord 23 made of nylon for fastening the belts 21 and 22 is spirally wound around the outer sides of the first and second belts 21 and 22. A tread 24 is provided outside the cap cord 23. The tread 24 is composed of two members, an inner base tread 25 having different required performances and an outer cap tread 26 in contact with the road surface. The cap tread 26 in contact with the road surface is made of rubber having excellent wear resistance, and has a base. The tread 25 is made of rubber having a property of suppressing heat generation. The first and second belts 21 and 22, the cap cord 23, and the tread 24 constitute an outer element 27 of the tire 10.

  Side walls 29 are provided on both side surfaces of the tire 10 between the inner element 17 and the outer element 27. The tire 10 is mainly composed of the constituent members described above.

  Next, a raw tire molding apparatus 100 that molds the raw tire 10A that is the basis of the tire 10 will be described with reference to FIGS.

  As shown in FIG. 3A, the green tire forming station 1st is provided with a forming drum 31, and a pair of left and right ring-shaped moving bodies 32 are placed on the forming drum 31 by the driving means CY1. It is supported so as to be relatively close to and away from the axial direction. A pair of left and right first bladder supports 33 is supported on each moving body 32 so as to be relatively movable in the axial direction of the forming drum 31 by each driving means CY2. Each of the first bladder supports 33 is divided into a plurality of support pieces 33a on the circumference so as to be movable in the radial direction, and each of the support pieces 33a is engaged with an inclined cam 36 formed on each of the movers 32. Has been. Therefore, the pair of left and right first bladder supports 33 can be moved in the radial direction simultaneously with the movement in the axial direction.

  The left and right pair of first bladder supports 33 are fixed to the peripheral edge portions of the inner flexible film 34 made of a thin cylindrical rubber elastic body that can be expanded and contracted by pressurized air. Further, the peripheral edges of the aggregate layer 35 are fixed to each first bladder support 33 so as to surround the outer periphery of the inner flexible membrane 34. The central portion of the aggregate layer 35 and the central portion of the inner flexible membrane 34 are coupled to each other so that they cannot be separated.

  On the molding drum 31, a pair of left and right second bladder supports 38 are supported by the driving means CY3 so as to be relatively close to and away from each other in the axial direction of the molding drum 31. These second bladder supports 38 are arranged on both sides of each first bladder support 33 so as to sandwich the inner flexible membrane 34 and the aggregate layer 35 from both sides in the axial direction. Between the pair of left and right second bladder supports 38, an outer flexible film 37 that can be expanded and contracted by pressurized air is fitted, and both ends of the outer flexible film 37 are respectively connected by engagement pins (not shown). The second bladder support 38 is detachably coupled. Then, in a state where the outer flexible film 37 is fitted between the second bladder supports 38, as shown in FIG. A three-layer bladder 50 covered with the flexible film 37 is formed. A mold release agent is provided on the outer surface of the outer flexible membrane 37 that contacts the inner surface of the green tire 10A so that it can be easily separated from the inner surface of the vulcanized tire 10B (see FIG. 10A) after vulcanization. Is applied.

  The bladder 50 described above functions so that the three of the inner flexible film 34, the aggregate layer 35, and the outer flexible film 37 cooperate to expand and expand the diameter of the tire 10A when the tire 10A is molded. During vulcanization of 10A, the outer flexible membrane 37 is separated from the inner flexible membrane 34 and the aggregate layer 35 so that only the outer flexible membrane 37 maintains the shape of the tire 10A until vulcanization is completed. Function. That is, the outer flexible film 37 functions as a bladder for both molding and vulcanization.

  An annular partition member 39 made of elastic rubber is provided between each of the left and right moving bodies 32 and the left and right first bladder supports 33, and these partition members 39 provide the first bladder support 33 with the partition members 39. A space S1 surrounded by the supported inner flexible film 34 and the outer flexible film 37 supported by the second bladder support 38 is surrounded by a pair of left and right movable bodies 32 and the inner flexible film 34. The space portion S2 is separated and partitioned.

  As shown in FIGS. 3B and 3C, the outer flexible film 37 is supported by cylindrical bodies 41 and 42 made of a rigid body such as metal that can approach and be separated from each other. Between 41 and 42, it is comprised with the flexible film | membrane which exhibits the elastic action of the thin cylindrical shape which can be expanded / contracted by pressurized air. The peripheral edge portions of both ends of the outer flexible film 37 are integrally held by holding portions 41a and 42a provided at outer end portions of the cylindrical bodies 41 and 42, respectively.

  The outer flexible membrane 37 is configured such that the inner ends of the cylindrical bodies 41 and 42 are in contact with each other so that the inside of the outer flexible membrane 37 can be sealed so that the expanded state can be maintained. That is, as shown in detail in FIG. 5, the inner end portions of the cylindrical bodies 41 and 42 can come into contact with each other in a polymerized manner, and one of these inner end portions is expanded or contracted in the radial direction by a spring force. A possible ring-shaped locking member 44 is held, and on the other side, an annular groove 45 is provided for releasably engaging with the locking member 44. Further, a seal ring 46 that seals the contact surface is provided on one of the inner ends of the cylindrical bodies 41 and 42. The locking member 44, the annular groove 45, and the seal ring 46 constitute a hermetic seal means 47 that hermetically seals the inside of the outer flexible film 37, and the hermetic seal means 47 provides a sealed state inside the outer flexible film 37. Hold. The hermetic sealing means 47 is released when a certain external force is applied to overcome the spring force of the locking member 44 in the direction in which the cylindrical bodies 41 and 42 are separated from each other.

  As shown in FIGS. 4 (C) and 4 (D), the toroidal left-right symmetry provided to the tire 10A is provided around the forming drum 31 when the tire 10A swells and expands and when the raw tire moves. In order to ensure the accuracy and the like more accurately, a holder 48 having a concave section that temporarily holds the outer peripheral surface and both side surfaces of the tire 10A at several points on the circumference is provided to be movable in the radial direction. .

  FIG. 6 is a schematic view showing the above-described aggregate layer 35 in a developed state. The aggregate layer 35 is composed of a plurality of yarns 51 having high tensile strength and not extending. Is formed of an aramid fiber such as Kevlar and has a property of being easily bent. The aggregate layer 35 includes a first yarn group 52 disposed along the circumferential direction of the bladder 50 so that the bladder 50 has a predetermined toroidal shape when the bladder 50 is expanded and expanded. The second yarn group 53 disposed along the direction intersecting the first yarn group 52 is formed in a lattice shape.

  The respective yarns 51 constituting the first yarn group 52 are arranged in parallel with each other along the circumferential direction of the bladder 50, and each of these yarns 51 is located at an intermediate portion in the axial direction of the bladder 50. The longer the yarn 51 located at both ends, the shorter the yarn 51. Further, in each yarn 51 constituting the second yarn group 53, the interval between both ends of the adjacent yarn 51 is narrow, and the interval between the intermediate portions is wide. Thus, when the bladder 50 is bulged and expanded, the length of each thread 51 constituting the aggregate layer 35 and the aggregate layer 35 so that the aggregate layer 35 has a predetermined toroidal shape set in advance. An array structure is set. The first yarn group 52 and the second yarn group 53 are coupled to each other at the intersection of the respective yarns 51 by sewing, thermocompression bonding, an adhesive, or the like.

  As a result, when pressurized air is supplied to the inside of the bladder 50 having the three-layer structure and the bladder 50 is expanded and expanded in diameter, the aggregate layer 35 is shown in detail in FIGS. 4 (A) and 7. It is formed in a preset shape, that is, a toroidal shape close to the tire shape after vulcanization. Since each thread 51 constituting the aggregate layer 35 has high tensile strength and does not stretch, it does not stretch as the bladder 50 bulges and expands, and the aggregate layer 35 has a predetermined toroidal shape. Is securely held for a long time.

  Thus, the three-layered bladder 50 having the aggregate layer 35 forms the tire 10A in a predetermined toroidal shape. This toroidal shape is formed by removing the aggregate layer 35 from the inside of the tire 10A during vulcanization, Even if only the flexible membrane 37 is formed, the shape is maintained by the pressure held in the outer flexible membrane 37.

  That is, after forming the raw tire, the pressurized air supplied into the inner flexible membrane 34 of the bladder 50 in order to bulge and expand the bladder 50 is changed to the outer flexible membrane by switching the switching valve (not shown). The aggregate layer 35 and the inner flexible membrane 34 are contracted and contracted to be separated from the outer flexible membrane 37. Therefore, after the tire molding, as shown in FIG. 8, the tire 10A is fed into the vulcanization station 2st in a state in which only the outer flexible film 37 is incorporated.

  Next, a vulcanizing apparatus 200 for vulcanizing the green tire 10A molded as described above will be described with reference to FIGS.

  In the vulcanization station 2st, as shown in FIG. 9A, the openable and closable mold apparatus 55 constituting the vulcanization apparatus 200 and steam in the raw tire 10A positioned in the mold apparatus 55 are provided. A heating / pressurizing fluid supply means (not shown) for supplying a heating / pressurizing fluid, etc., and a heating means (not shown) embedded in the mold apparatus 55 are provided. The mold device 55 includes a pair of left and right side wall molds 56 that are fixed to be concentric with the mold center line, and a pair of sidewall molds 56 that are supported around the mold center line so as to be movable back and forth in a radial direction. The upper eight divided tread molds 57 are configured. The split tread mold 57 has an arc shape having an arc length of a predetermined angle. A tread forming surface on which a predetermined tread pattern is formed is formed at the center of the inner surface, and sidewall metal molds are formed at both ends of the inner surface. A circular arc surface joined to the outer peripheral surface of the mold 56 is formed. The pair of left and right sidewall molds 56 and the divided tread mold 57 are opened and closed by a mold opening / closing means (not shown).

  A method for manufacturing the tire 10 shown in FIG. 1 using the tire forming apparatus 100 and the vulcanizing apparatus 200 described above will be described below mainly based on FIGS. 3, 4, 9 and 10.

  In the initial state shown in FIG. 3A, an outer flexible membrane 37 is shown on the outer periphery of the inner flexible membrane 34 and the aggregate layer 35 provided on the forming drum 31, as shown in FIG. It is supplied from the right side of the figure by a substantially bladder supply device. The cylindrical bodies 41 and 42 at both ends of the outer flexible film 37 are fitted and supported by a pair of second bladder supports 38, and the cylindrical bodies 41 and 42 are respectively attached to the second bladder support 38 by engagement pins (not shown). Integrally engaged. In this state, a bladder 50 having a three-layer structure in which the inner flexible film 34, the aggregate layer 35, and the outer flexible film 37 are arranged in this order from the inner peripheral side is configured.

  Subsequently, the inner element 17 of the tire 10 is carried into the outer circumference of the outer flexible membrane 37, that is, the outer circumference of the bladder 50 having a three-layer structure, from the left side of the drawing by a tire part carrying-in device (not shown) in a cylindrical state. (FIG. 3C), the bladder 50 is positioned at the center position in the axial direction. When the inner element 17 is carried into a predetermined position, the pair of left and right first bladder supports 33 are moved inward along the axial direction by the driving means CY2. Due to the movement of the first bladder support 33, the plurality of circumferential support pieces 33a constituting each first bladder support 33 ride on the inclined cams 36 provided on the respective movement bodies 32 and outward in the radial direction. Moved. As a result, as shown in FIG. 3D, the first bladder support 33 is pressed against each of the bead portions 16 of the inner element 17 via the outer flexible film 37, and the inner element 17 is against the bladder 50. Positioned and clamped.

  Next, from the first air hole 61 (see FIG. 4A) opened in the axial center of the forming drum 31, the internal space (inside the inner flexible film 34) of the bladder 50 having the three-layer structure is interposed through the space S2. Since the pair of moving bodies 32 are synchronously moved in the direction approaching each other by the driving means CY1, the first bladder support 33 is also moved integrally with the moving body 32. . At the same time, the second bladder support 38 is also moved in a direction approaching each other synchronously with the first bladder support 33 by the driving means CY3. As a result, as shown in FIG. 4A, both bead portions 16 of the inner element 17 are moved toward each other, and the bladder 50 between the bead portions 16 is moved outward by the pressurized air. It is expanded. For this purpose, the outer surface of the bladder 50 (outer flexible film 37) is in close contact with the inner peripheral surface of the body ply 13 of the inner element 17, and the body ply 13 is swelled and expanded. The diameter of the body ply 13 is expanded to a required shape, and the end of the body ply 13 is bent by a bending tool (not shown).

  In this case, the bladder 50 having the three-layer structure is provided with the aggregate layer 35 that forms a toroidal shape by bulging and expanding the diameter. It will be formed in a shape.

  Thereafter, on the outer surface of the body ply 13 of the inner element 17 formed in a toroidal shape, the first and second belts 21 and 22 constituting the outer element 27 of the tire 10, the cap cord 23, the tread 24, the sidewall 29, etc. Are joined together, or the side walls 29 are pasted together with the outer elements 27 integrated in advance, and the formation of the pre-vulcanized tire, that is, the green tire (green tire) 10A is completed.

  Subsequently, the supply of pressurized air is switched by a not-illustrated switching valve, and the flexible outer side of the bladder 50 is passed through the space S1 from the second air hole 62 (see FIG. 4B) opened in the molding drum 31. Pressurized air is supplied between the membrane 37 and the aggregate layer 35. As a result, as shown in FIG. 4B, the aggregate layer 35 and the inner flexible membrane 34, which are coupled to each other at the center, are separated from the outer flexible membrane 37, and between the first bladder supports 33. Stored. In this way, when the aggregate layer 35 and the inner flexible membrane 34 are separated from the outer flexible membrane 37, each first bladder support 33 is moved in the opposite direction by the driving means CY2, and on the circumference. The plurality of support pieces 33a are moved radially inward along the inclined cams 36 provided in the respective moving bodies 32, and are separated from the outer flexible film 37 as shown in FIG. Further, a plurality of holders 48 on the circumference are moved radially inward to temporarily hold the outer peripheral surface and both side faces of the tire 10A from several places on the circumference, and the symmetry of the toroidal shape applied to the tire 10A Assistance to ensure sex more accurately.

  Thereafter, the moving body 32 and the second bladder support 38 are relatively moved by the driving means CY1 and CY3 in a direction approaching each other. As a result, the first bladder support 33 together with the moving body 32 is held in the state closest to the axial center of the molding drum 31, while the second bladder support 38 and the cylindrical body 41 of the outer flexible membrane 37, Since 42 is also relatively moved in the approaching direction, the inner end portions of the cylindrical bodies 41 and 42 are overlapped with each other by the hermetic sealing means 47 and sealed. As a result, as shown in FIG. 4D, the inside of the outer flexible film 37 is kept in a sealed state, so that the pressurized state is also maintained in the tire 10A bulging and expanding in a toroidal shape. The state is maintained until the tire 10A is vulcanized.

  Therefore, the tire 10 </ b> A once formed in a toroidal shape by the bladder 50 does not collapse even after the aggregate layer 35 is removed, and the toroidal shape is maintained by the presence of the outer flexible film 37.

  When the outer flexible film 37 is closed so that the inner ends of the cylindrical bodies 41 and 42 are in contact with each other, both ends of the outer flexible film 37 are connected to the tire 10A as shown in FIG. It will be bent spherically at the inner ends of both sides.

  Next, the raw tire 10A is detached from the molding drum 31 and conveyed to the vulcanization station 2st in a state in which the raw tire 10A incorporates the outer flexible membrane 37 in which the inside is sealed (FIG. 8). It is set at a predetermined position in the mold apparatus 55.

  When the tire 10A is set at a predetermined position of the vulcanizing station 2st, as shown in FIG. 9A, the pair of left and right sidewall molds 56 are moved to positions where the tire 10A is sandwiched by a moving device (not shown). Next, as shown in FIG. 9 (B), the eight divided tread molds 57 on the circumference are moved radially inward from the open position and are crimped to the outer peripheral surface (tread 24) of the tire 10A. Moved to position. In this closed position, the inner circumferential arc surface of each divided tread mold 57 forms a continuous circle in the circumferential direction and is in close contact with the outer circumferential surface of the tire 10A.

  Subsequently, as shown in FIG. 9C, the pair of cylindrical bodies 41 and 42 of the outer flexible film 37 are moved away from each other, whereby the hermetic seal means 47 is released and the outer flexible film 37 is released. The sealed state in the inside 37 is released, and the pressurized fluid is exhausted from the inside of the outer flexible membrane 37. In this state, a heated pressurized fluid such as steam is introduced into the outer flexible film 37. Next, one side wall mold 56 is moved and pressed against one side surface of the tire 10A to be vulcanized, and the other side wall mold 56 is moved to the other side surface of the tire 10A. The tire 10A is clamped by pressing (FIG. 9D).

  In this case, prior to clamping the tire 10 </ b> A, the pair of cylindrical bodies 41, 42 may be separated, the sidewall mold 56 may be tightened at the same time, and then the divided tread mold 57 may be brought into close contact with each other almost simultaneously. .

  That is, when the tire 10A is set at a predetermined position of the vulcanization station 2st, the sidewall mold 56 is moved to a position where the tire 10A is sandwiched, and then the pair of cylindrical bodies 41, 42 of the outer flexible film 37 are mutually connected. Simultaneously with the movement in the separating direction, the pair of left and right sidewall molds 56 are further moved to clamp the tire side surfaces. At the same time, each divided tread mold 57 is brought into close contact.

  In this state, the inner surface of the tire 10 </ b> A is evenly passed through the outer flexible membrane 37 by a heated and pressurized fluid such as high-temperature and high-pressure steam introduced into the outer flexible membrane (molding and vulcanization bladder) 37. The tire is pressed by a strong force and heated and pressed by the heating means embedded in the sidewall mold 56 and the divided tread mold 57, so that the raw tire ( Green tire) 10A is vulcanized. By such vulcanization treatment, elasticity and durability are generated in the rubber of the green tire, and a required tread pattern is formed on the outer surface of the tread 24.

  When the vulcanization process is completed after a lapse of a predetermined time, the heated and pressurized fluid in the vulcanized tire 10B and the outer flexible film 37 is discharged to the outside, and the pair of cylindrical bodies 41 of the outer flexible film 37 is discharged. , 42 are moved in a direction approaching each other, and the inside of the outer flexible membrane 37 is kept sealed again. At the same time, as shown in FIGS. 10A and 10B, the mold opening of the mold apparatus 55 is started, whereby the pair of left and right sidewall molds 56 are retracted and returned in a direction away from each other. The divided tread mold 57 is returned and returned to the open position radially outward. Thereafter, the vulcanized tire 10B is detached from the mold apparatus 55, and the P.P. C. It is sent to an I (Post Cure Inflation) machine and inflated and cooled, thereby completing the production of the tire 10.

  In such a vulcanization process, the green tire 10A is maintained in a toroidal shape by the outer flexible film 37, so that the centering and the left-right symmetry of the tire 10A are well secured, and the shape of the preset tire is set. The vulcanized tire 10B can be easily obtained.

  In this way, when the manufacture of the tire 10 is completed, the outer flexible membrane 37 that is pulled in the direction in which the cylindrical bodies 41 and 42 of the outer flexible membrane 37 are separated from each other and is in close contact with the inner surface of the vulcanized tire 10B. Is separated from the inner surface of the tire 10B and detached from the inside of the tire 10B, and as shown in FIG. Thereafter, the vulcanized tire 10B is carried out of the vulcanizer by the tire conveying device, and the outer flexible film 37 is forwarded to the bladder supply device, and the vulcanization process at the vulcanization station 2st is completed.

  The outer flexible film 37 can be detached from the vulcanized tire 10B by being easily separated from the tire inner surface by applying a release agent to the surface that is in close contact with the tire inner surface.

  When the raw tire 10A is detached from the forming drum 31 with the outer flexible film 37 incorporated (FIG. 8), the pair of second bladder supports 38 are separated from each other at the forming station 1st. It is moved to return to the original position shown in FIG. 3A, and the first bladder support 33 is moved together with the pair of moving bodies 32 in a direction away from each other to return to the original position. In that state, another outer flexible membrane 37 is supplied to the outer periphery of the inner flexible membrane 34 and the aggregate layer 35 by the bladder supply device, and the molding of the next tire has been described with reference to FIGS. In the same manner, the process is started in parallel with the vulcanization process.

  In the above-described embodiment, the example in which the bladder 50 having the three-layer structure is configured by the inner flexible film 34, the aggregate layer 35, and the outer flexible film 37 that are independent from each other has been described. The material layer 35 does not necessarily have to be provided independently. For example, the inner flexible film 34 and the aggregate layer 35 can be configured inseparably by attaching a rubber film integrally to one side of the aggregate layer 35. It is.

  In the above-described embodiment, after the green tire 10A is molded, the outer flexible film 37 is sealed by the hermetic sealing means 47 in order to maintain the pressure in the tire 10A and maintain the toroidal shape. However, the structure of the hermetic seal means 47 is not limited to that of the embodiment, and various structures that can fulfill the function can be applied.

  Furthermore, in the above-described embodiment, an example in which the vulcanized tire 10B is fed into the PCI machine with the outer flexible film 37 incorporated therein and expanded and cooled has been described. However, after vulcanization, the vulcanized tire 10B is The outer flexible film 37 may be removed after the mold device 55 is removed from the mold apparatus 55, and only the vulcanized tire 10B may be subjected to PCI.

1 is a schematic cross-sectional view of a tire showing an embodiment of the present invention. It is a figure which shows the components which comprise the tire of FIG. It is a figure which shows the process in the molding station which shape | molds a green tire. It is a figure which shows the process in the molding station which shape | molds a green tire. It is a figure which shows an example of the sealing means of an outer side flexible membrane. It is a schematic plan view which expand | deploys and shows an aggregate layer. It is a partially broken perspective view which shows a bladder. It is a figure which shows the state of the green tire before vulcanization. It is a figure which shows the process in the vulcanization station which vulcanizes a green tire. It is a figure which shows the process in the vulcanization station which vulcanizes a green tire.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Complete tire, 10A ... Raw tire, 10B ... Vulcanized tire, 13 ... Body ply, 16 ... Bead part, 17 ... Inner element, 24 ... Tread, 27 ... Outer element, 29 ... Side wall, 31 ... Molding drum, 32 ... Moving body, 33 ... First bladder support, 34 ... Inner flexible membrane, 35 ... -Aggregate layer, 37 ... outer flexible membrane, 38 ... second bladder support, 39 ... partition member, 41, 42 ... cylindrical body, 44 ... locking member, 45 ..Annular groove, 46... Seal ring, 47... Sealing sealing means, 48... Holder, 51. Thread group, 56 ... sidewall mold, 57 ... split tread mold, 100 ... tire molding device, 200 ... Vulcanizing apparatus, 1st · · · forming station, 2st · · · vulcanizing station.

Claims (7)

In a tire manufacturing method including a raw tire molding stage for assembling a raw tire by assembling an inner element and an outer element constituting a tire, and a vulcanization stage for vulcanizing the raw tire molded in the raw tire molding stage, A tire manufacturing method comprising manufacturing tires by sequentially performing steps 1) to (5).
(1) A state where an outer flexible membrane for molding and vulcanization is fitted on a molding drum having an inner flexible membrane and an aggregate layer, and the inner element is fitted on the outer peripheral side of the outer flexible membrane. Then, the inner element is formed into a predetermined shape by expanding and expanding the bladder having a three-layer structure including the inner flexible membrane, the aggregate layer, and the outer flexible membrane,
(2) A green tire is formed by mounting the outer element on the outer side of the inner element formed in a predetermined shape,
(3) After forming the raw tire, the inner flexible membrane and the aggregate layer are contracted and shrunk with respect to the outer flexible membrane to separate the inner flexible membrane and the aggregate layer from the outer flexible membrane,
(4) Move in a state in which pressure is maintained in the outer flexible membrane, and then seal the heated and pressurized fluid in the outer flexible membrane, vulcanize the raw tire,
(5) After vulcanization, the outer flexible membrane is contracted and reduced in diameter, and the outer flexible membrane is separated from the inside of the tire after vulcanization.   In the molding step, a green tire is expanded and expanded in a toroidal shape with a bladder having a three-layer structure of the inner flexible membrane, the aggregate layer, and the outer flexible membrane, and in the vulcanization step, the outer flexible membrane is expanded. The tire manufacturing method according to claim 1, wherein the toroidal shape is maintained only by the above.   The aggregate layer is composed of a plurality of yarns having high tensile strength and not extending. The yarns are arranged along the circumferential direction, and the first yarn group. And a second thread group arranged along the direction intersecting with the grid, and configured to have a preset toroidal shape when the three-layered bladder bulges and expands. The tire manufacturing method according to claim 1 or 2, wherein   After the molding step, the outer flexible membrane is separated from the inner flexible membrane and the aggregate layer, and the inside of the outer flexible membrane is sealed to maintain the toroidal shape, and the raw tire is vulcanized in that state. The method for manufacturing a tire according to any one of claims 1 to 3, wherein the tire manufacturing method is carried out.   In a raw tire molding apparatus that forms a raw tire by assembling an inner element and an outer element that constitute a tire, an outer part that is used for molding and vulcanization that is fitted on the outer periphery of a molding drum having an aggregate layer and an inner flexible film A pressurized gas in a bladder having a three-layer structure comprising the inner flexible membrane, the aggregate layer, and the outer flexible membrane in a state where the inner element is fitted on the outer periphery of the flexible membrane and the outer flexible membrane. Means to bulge and expand the bladder to form the inner element in a toroidal shape, and to fit the outer element on the outside of the toroidal inner element and to bring the inner element and the outer element into close contact with each other A raw tire generating means for generating a raw tire, and an aggregate layer and an inner flexible membrane are contracted and reduced in diameter with respect to the outer flexible membrane, and the outer flexible membrane is separated from the aggregate layer and the inner flexible membrane. Separated from the separation means, aggregate layer and inner flexible membrane The outer flexible membrane is hermetically sealed to maintain a toroidal shape, and the conveying means for conveying the raw tire to the vulcanization process while being sealed by the sealing means. Raw tire molding equipment.   6. The raw tire molding apparatus according to claim 5, wherein the outer flexible membrane is supported by a pair of cylindrical bodies whose both end portions can approach and separate from each other. The sealing means seals the inside of the outer flexible membrane by the inner ends being abutted and locked to each other by movement of the pair of cylindrical bodies of the outer flexible membrane toward each other. 7. The raw tire molding apparatus according to claim 6, further comprising a hermetic sealing means that is unlocked by movement in a direction away from each other.

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