JP2010125675A - Apparatus for manufacturing pneumatic tire and method for manufacturing pneumatic tire - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an apparatus for manufacturing a pneumatic tire which is small in size and inexpensive, and yet easily improved in work efficiency. <P>SOLUTION: A transportation means 18 has an upper support 19 whose upper surface 19a is convexedly curved upward, a lower support 22 which is flat and has a distance to the top of the upper support 19 roughly equal to the diameter of a ply band 15, and connector 25 which connects the upper support 19 with the lower support 22. The upper support 19 is inserted in the ply band 15 and support the ply band 15 from the inside. This arrangement allows the total height of the transportation means 18 to be slightly higher than the diameter of the ply band 15 and its total width to be narrower than the diameter of the ply band 15. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

    The present invention relates to an apparatus and a manufacturing method for manufacturing a pneumatic tire, particularly a large pneumatic tire to be mounted on a large construction machine or the like.

As a conventional pneumatic tire manufacturing apparatus, for example, a device described in Patent Document 1 below is known.
JP 2000-202923 A

  This includes a band forming drum for forming a cylindrical ply band by winding at least a carcass ply around the periphery, a conveying means for conveying the ply band from the band forming drum to the first forming drum, and a first forming drum. The narrowing means for narrowing the axially outer sides of the ply band conveyed to the bead, the bead setting means for setting the bead core in the step part of the ply band formed by the narrowing, and the ply band axially outside the bead core around the bead core And folding means for folding back.

  The conveying means of the manufacturing apparatus includes a cylindrical annular body having an inner diameter larger than that of the ply band, a plurality of moving members supported by the annular body so as to be movable in a radial direction, and each of the moving members. A vacuum cup supported at the inner end in the radial direction, and when the ply band is transported, the outer peripheral surface of the ply band is adsorbed by the vacuum cup so that the ply band is gripped from the outer side in the radial direction.

    However, in such a conventional pneumatic tire manufacturing apparatus, when the pneumatic tire to be manufactured is a large pneumatic tire mounted on a large construction vehicle or the like as described above, an annular body The diameter becomes a very large diameter of several meters, and as a result, there is a problem that the whole conveying means becomes large and the manufacturing cost becomes expensive. Further, in order to grip a large ply band, it is necessary to increase the number of vacuum cups to be installed, but the possibility of failing in adsorption increases as the number of installations increases. If the adsorption fails, the ply band hangs down and is caught on the first molding drum. In such a case, the ply band is adsorbed by the vacuum cup that is manually removed by the operator. As a result, there was a problem that the work efficiency was lowered.

  An object of the present invention is to provide a pneumatic tire manufacturing apparatus and a pneumatic tire manufacturing method capable of easily improving work efficiency while being small in size and inexpensive in production cost.

    Such an object is as follows. First, a band forming drum for forming a cylindrical ply band by winding at least a carcass ply around the periphery, and a conveying means for conveying the ply band from the band forming drum to the first forming drum. And a narrowing means for narrowing both axially outer side portions of the ply band conveyed to the first forming drum, a bead setting means for setting a bead core at a step portion of the ply band formed by the narrowing, and an outer side in the axial direction from the bead core In the pneumatic tire manufacturing apparatus comprising the folding means for folding the ply band around the bead core, the conveying means is inserted in the ply band in the axial direction, and the upper surface is gently curved in a convex shape upward. And an upper support that supports the upper end portion of the ply band from the inside by the upper surface; A flat lower support, which is installed immediately below the support, and whose distance from the upper surface to the upper end of the upper support is substantially equal to the diameter of the ply band, and a connection that extends in the vertical direction and connects the upper and lower supports to each other. This can be achieved by a pneumatic tire manufacturing apparatus having a body.

  Second, a step of forming a cylindrical ply band by winding at least a carcass ply around the band forming drum, a step of conveying the ply band from the band forming drum to the first forming drum by a conveying means, The step of narrowing the axially outer side portions of the ply band conveyed to the forming drum by the narrowing means, the step of setting the bead core by the bead setting means at the stepped portion of the ply band formed by the narrowing, and the outer side of the bead core in the axial direction And a step of folding back the ply band around the bead core by a folding means, wherein the conveying means includes an upper support whose upper surface is gently curved upwardly, and A flat bottom where the distance from the upper surface to the upper edge of the upper support is approximately equal to the diameter of the ply band. When having a holding body and a connecting body extending in the vertical direction and connecting the upper and lower support bodies to each other, the upper support body is inserted into the ply band in the axial direction, and the upper end portion of the ply band is This can be achieved by a method for manufacturing a pneumatic tire that is supported from the inside by the upper surface of the upper support.

  In this invention, the conveying means has a flat upper surface whose upper surface is gently curved upward and a flat surface whose distance from the upper surface to the upper end of the upper support is substantially equal to the diameter of the ply band. A lower support body, and a connecting body that extends in the vertical direction and connects the upper and lower support bodies to each other. The upper support body is inserted into the ply band in the axial direction to support the upper end portion of the ply band. Since the upper surface of the body is supported from the inside, the overall height of the conveying means can be suppressed to a level slightly higher than the diameter of the ply band, and the overall width can be suppressed to a value narrower than the diameter of the ply band. As a result, the entire conveying means can be downsized and the manufacturing cost can be reduced.

  Moreover, when the ply band is supported, the ply band is hooked on the upper support and suspended from the upper support, so that there is no failure in support, and as a result, the work efficiency is improved. In addition, when the lower end portion of the ply band is deformed flat while being in contact with the lower support body, and is supported from below by the lower support body, Is reduced, thereby effectively suppressing the elongation of the rubber between the carcass cords at these portions.

  According to the second aspect of the present invention, when the ply band is transferred to the conveying means, the ply band is rotated around the axis so that the upper support can be easily moved in the axial direction toward the coupling body. Thus, the transfer operation is facilitated. In addition, the lengths of the ply bands located on one side and the other side of the upper support after the transfer can be easily adjusted, for example, substantially the same.

  Here, when the ply band is supported by the upper support as described above, if the lower end portion of the ply band comes into contact with the lower support and is deformed flat, the lower end portion (flat portion) A slack portion with a small curvature may occur at both ends, but a large compressive strain occurs in such a slack portion, so that the rubber gauge between the carcass cords becomes narrow, and the spacing between the carcass cords becomes coarse. Thereafter, both ends of the ply band in the axial direction are narrowed down by the narrowing means as described above. At this time, a wave with a large amplitude is generated in the portion where the above-described carcass cord interval is dense, and this wave is wrinkled in a later process. End up.

  However, as described in claim 3, by inflating the pressing body, both end portions of the pressing body protrude laterally from both ends in the width direction of the upper support, or as described in claim 4, If the length in the longitudinal direction of the pressing body is made larger than the width of the upper support, and the both ends of the longitudinal direction are protruded laterally from the both lateral ends of the upper support by rotating the pressing body, these pressing The ply band can be deformed so that the ply band approaches a circular shape by extruding the vertical middle portion of the ply band toward the outside in the width direction of the upper support by the body. As a result, the slack portions at both ends of the lower end portion of the ply band disappear, and the occurrence of waviness and wrinkles due to narrowing can be effectively suppressed.

  On the other hand, when the ply band is transferred to or taken out from the conveying means, in claim 3, the pressing body is contracted to accommodate the pressing body in the width of the upper support, whereas in claim 4, The width of the pressing body is smaller than the width of the upper support, and the pressing body is rotated and stored within the width of the upper support, thereby avoiding interference between the pressing body and the ply band. To be smooth. Moreover, if comprised as described in Claim 5, a press body can be lightweight and can simplify a structure.

Embodiment 1 of the present invention will be described below with reference to the drawings.
In FIGS. 1 and 2, reference numeral 11 denotes a band forming machine installed on the floor surface 12, and this band forming machine 11 includes a driving unit 13 and a band forming capable of expanding and contracting that is rotatably supported by the driving unit 13. The band forming drum 14 has a drum 14 and can receive a driving force from the driving unit 13 and rotate around a horizontal axis. When the band forming drum 14 is rotating, at least the carcass ply is supplied to the band forming drum 14, and an inner liner, rubber chafer, hat rubber, wire chafer, etc. The ply band 15 is formed.

  18 is a conveying means for conveying the ply band 15 from the band forming drum 14 to the first forming drum, which will be described later. The conveying means 18 is gently curved with an upper surface 19a upwardly convex, here in an arc shape. The upper support 19 extends horizontally, and the radius of curvature of the upper surface 19a is smaller than the radius of curvature of the ply band 15, which is approximately 2/3 here. The length of the upper support 19 is larger than the length of the ply band 15 in the axial direction, while its width is smaller than the diameter of the ply band 15 and is about the radius.

  The upper support 19 supports a plurality of rollers 21 that freely rotate around an axis parallel to the axis of the upper support 19, and these rollers 21 are distributed almost uniformly on the upper support 19. A part thereof protrudes from the upper surface 19a of the upper support 19 by the same amount. Reference numeral 22 denotes a flat, substantially rectangular plate-like lower support that is installed directly below the upper support 19 and extends parallel to the upper support 19, and the lower surface of the lower support 22 rolls on the floor surface 12. A plurality of movable rolling wheels 23 are rotatably supported. The upper surface 22a of the lower support 22 is a flat surface, and the distance from the upper surface 22a to the upper end of the upper support 19 (upper surface 19a) is substantially equal to the diameter of the ply band 15.

  Reference numeral 25 denotes a connecting body extending in the vertical direction. The upper end of the connecting body 25 is connected to the base end of the upper support 19, while the lower end is connected to the base end of the lower support 22. Thus, the upper support 19 and the lower support 22 are connected to each other by the connecting body 25. In addition, the lower supports 19 and 22 and the connecting body 25 as a whole constitute the conveying means 18 for conveying the ply band 15 from the band forming drum 14 to the first forming drum described later. When the ply band 15 is conveyed using the conveying means 18, the upper support 19 of the conveying means 18 is inserted into the horizontal ply band 15 in the axial direction, in other words, the upper support 19 The ply band 15 is fitted to the outside of the ply band 15 and the upper end portion of the ply band 15 is supported from the inner side (lower side) by the upper support 19 of the conveying means 18.

  In this way, if the conveying means 18 is composed of the upper and lower supports 19, 22 and the connecting body 25, and the upper end portion of the ply band 15 is supported from the inside by the upper surface 19a of the upper support 19, the conveying means The overall height of 18 can be suppressed to a level slightly higher than the diameter of the ply band 15 and the overall width can be suppressed to a value narrower than the diameter of the ply band 15. As a result, the entire conveying means 18 can be downsized and the manufacturing cost can be reduced. It can be inexpensive. In addition, when the ply band 15 is supported, the ply band 15 is hooked on the upper support 19 and suspended from the upper support 19, so that there is no failure in support, and as a result, the work efficiency is improved.

  Here, the transfer operation of the ply band 15 from the band forming drum 14 to the conveying means 18 is performed by using, for example, a transfer means (not shown) or manually performed by an operator. When the worker performs the work, if the ply band 15 is for a large pneumatic tire mounted on a large construction vehicle or the like, the work is difficult because the weight is heavy.

  However, if a plurality of rollers 21 are provided on the upper support 19 as described above, the ply band 15 is brought into contact with the rollers 21 when the ply band 15 is transferred from the band forming drum 14 to the conveying means 18. By rotating around the axis, the upper support 19 can be easily moved in the axial direction toward the connecting body 25 (base end), thereby facilitating the transfer operation. Further, the length of the ply band 15 located on one side and the other side of the upper support 19 after the transfer can be easily adjusted by the roller 21, for example, can be made substantially the same. The ply band 15 is taken out from the conveying means 18 in a subsequent process and transferred to the first forming drum. At this time as well, the transfer operation by the operator is facilitated.

  Then, when the ply band 15 is transferred to the conveying means 18 as described above, only the upper end portion of the ply band 15 is supported from below by the upper support body 19, and the other portions are shown by phantom lines in FIG. When the distance from the upper surface 22a of the lower support 22 to the upper end of the upper support 19 is substantially equal to the diameter of the ply band 15 as described above, the lower end of the ply band 15 is suspended. Comes into contact with the upper surface of the lower support 22 and deforms flatly, and the lower end of the ply band 15 is supported by the lower support 22 from below. As a result, the tensile strain due to the own weight at the upper end portion of the ply band 15 and the intermediate portion in the vertical direction is reduced, thereby effectively suppressing the elongation of the rubber between the carcass cords at these portions.

  However, as described above, when the lower end portion of the ply band 15 comes into contact with the upper surface 22a of the lower support 22 and is deformed flat, the bent portions 16 having a small curvature are formed at both ends of the lower end portion (flat portion) of the ply band 15. However, since a large compressive strain is generated in such a bending portion 16, the rubber gauge between the carcass cords is narrowed, resulting in a coarse and dense space between the carcass cords. When it becomes necessary for the ply band 15 to be temporarily stored in the transport means 18 for convenience, the degree of density becomes large. If the both ends in the axial direction of the ply band are narrowed down by the narrowing means in this state, a large amplitude undulation is generated at the portion where the cord interval is dense, and this undulation will be wrinkled in the subsequent process. It is.

  For this reason, in this embodiment, a hollow pressing body 28 that can be expanded and contracted by injecting and discharging a gas, for example, air, is provided between the upper support 19 and the lower support 22. Here, the pressing body 28 has an elliptical ring shape in which a cylindrical shape is crushed in the vertical direction, and the central axis of the ellipse is on the upper support 19 via a support tool 29 that grips the upper end of the pressing body 28. It is supported so that it may become parallel.

  Then, when gas is injected into the pressing body 28 through the fluid passage 30 and expanded, the length of the pressing body 28 in the longitudinal direction (the major axis of the ellipse) is larger than the width of the upper support body 19, and here the ply band 15 Since both ends of the pressing body 28 are approximately the same length as the diameter, the both ends of the pressing body 28 project laterally from both ends in the width direction of the upper support 19, and the middle part in the vertical direction of the ply band 15 hanging from the upper support 19 is formed. The ply band 15 is deformed so as to approach a circular shape by extruding toward the outer side in the width direction of the upper support 19. As a result, the bent portions 16 at both ends of the lower end portion of the ply band 15 disappear, and the occurrence of waviness and wrinkles due to narrowing can be effectively suppressed.

  On the other hand, when the gas is discharged from the pressing body 28 through the fluid passage 30 and contracted as indicated by phantom lines in FIG. 2, the longitudinal (ellipse major axis) length is smaller than the width of the upper support 19. The pressing body 28 is accommodated within the width of the upper support 19. As a result, the pressing body 28 can easily avoid interference with the ply band 15 hanging from the upper support body 19, transfer of the ply band 15 to the conveying means 18, and the transfer from the conveying means 18. The removal work can be made smooth. Further, if the pressing body 28 has an elliptical ring shape as described above, the pressing body 28 can be light and simple in structure. Here, the above-described pressing body 28 can be made of, for example, a rubber film reinforced with a cord made of organic fiber or the like.

  3 and 4, reference numeral 32 denotes a cylindrical first molding drum. The first molding drum 32 can be rotated around a horizontal axis by receiving a driving rotational force from a driving unit (not shown). The first forming drum 32 is composed of a plurality of arc-shaped segments. When these arc-shaped segments are synchronously moved in the radial direction by the operation of the link mechanism 33, the first forming drum 32 expands and contracts.

  When the ply band 15 is conveyed to the first molding drum 32 by the conveying means 18 described above, the ply band 15 is taken out from the conveying means 18 and then fitted to the outside of the first molding drum 32. . Thereafter, when the first molding drum 32 expands in diameter and supports the ply band 15 from the inside, the ply band 15 is transferred to the first molding drum 32. At this time, since the axial length of the ply band 15 is longer than the axial length of the first molding drum 32, the central portion 15a of the ply band 15 is slightly expanded radially outward by the first molding drum 32. While being supported from the inside, the axially outer side portions 15b project from the axially opposite ends of the first molding drum 32 to the axially outer side at the outer diameter during molding.

  Reference numeral 35 denotes a movable body having a cylindrical shape arranged on both outer sides in the axial direction of the first molding drum 32. These movable bodies 35 are moved in the axial direction by a driving mechanism (not shown), and the first molding drum 32 is moved. Can approach and separate. An axially outer end (base end) of a plurality (usually about 8 to 18) of swinging blades 36 extending substantially in the axial direction is rotatably connected to the inner end of each movable body 35. As a result, these oscillating blades 36 are respectively arranged on both outer sides in the axial direction of the first forming drum 32, and are oscillated radially outward by a drive spring (not shown) to the outer oscillating limit defined by the stopper. Can do.

  The oscillating blades 36 are disposed at an equal angular distance in the circumferential direction, and the cross-sectional shape is arcuate, so that the oscillating blades 36 can be in contact with the axially outer portion 15b of the ply band 15. 37 is a substantially cylindrical holding body, and these holding bodies 37 move in the axial direction separately from the movable body 35 by a driving force from a driving mechanism (not shown) and approach the first molding drum 32; Can be separated. Reference numeral 38 denotes a support body loosely fitted in the movable body 35. These support bodies 38 are connected to a holding body 37, and can move integrally with the holding body 37 in the axial direction.

  39 is a folded bladder locked in an airtight state on the outer periphery of each support 38, and these folded bladders 39 are usually contracted to form a cylindrical shape, but when a high-pressure fluid is supplied to the inside, It expands in a donut shape. Further, the holding body 37 has a can part 37a at its inner end in the axial direction, and the can part 37a can push down the folded folding bladder 39 inward in the axial direction. When the swinging blade 36 is positioned at the outer swing limit and the movable body 35 is positioned at the inner limit, when the holding body 37 moves inward in the axial direction, the holding body 37 is moved to the swinging blade 36. The oscillating blades 36 are synchronously oscillated inward in the radial direction.

  As a result, these oscillating blades 36 push the axially outer side portions 15b of the ply band 15 inward in the radial direction and narrow down (reduce the diameter) until they become slightly smaller in diameter than a bead core described later. At this time, a step 15c is formed at the boundary between the axial central portion 15a and the axial outer portion 15b of the ply band 15 and is bent along both axial end surfaces of the first forming drum 32. The swing blade 36 and the holding body 37 as a whole constitute a narrowing means 41 that narrows both axially outer side portions 15b of the ply band 15 conveyed to the first forming drum 32 until the diameter becomes smaller than the inner diameter of the bead core.

  Reference numeral 44 denotes a permanent magnet having a ring shape fixed to the can portion 37a. These permanent magnets 44 are circular, quadrangular, and hexagonal in cross section made of steel to which a filler 45 made of a substantially bowl-shaped unvulcanized rubber is attached. The square bead core 46 can be adsorbed and held by a magnetic force. When the aforementioned holding body 37 further moves inward in the axial direction, the bead core 46 with the filler 45 held by the permanent magnet 44 is pressed against the step portion 15c and passed to the ply band 15, thereby The bead core 46 is supplied and set to a predetermined position on the outer side of both end portions in the axial direction of the ply band 15, here, the step portion 15 c.

  The holding body 37 and the permanent magnet 44 having the can portion 37a described above constitute a bead setting means 47 for setting the bead core 46 to the step portion 15c of the ply band 15 formed by the narrowing down. As described above, when the bead core 46 is set in the step portion 15c, the movable body 35, the holding body 37, and the support body 38 move outward in the axial direction. Thereafter, the folded bladder 39 expands in a substantially donut shape, but at this time, the holding body 37 moves inward in the axial direction, pushes the folded bladder 39 inward in the axial direction, and the ply band 15 on the outer side in the axial direction from the bead core 46. Is folded around the bead core 46 as shown in FIG.

  The support body 38, the folding bladder 39, and the holding body 37 as a whole constitute folding means 48 that folds the ply band 15 axially outside the bead core 46 around the bead core 46. Here, the holding body 37 is shared by the narrowing means 41, the bead setting means 47, and the folding means 48 as described above. As a result, the structure is simple and can be manufactured at low cost.

  Next, after the holding body 37 and the support body 38 are moved outward in the axial direction, side treads are supplied and wound around the outer sides of both ends of the ply band 15 in the axial direction while rotating the first forming drum 32. As a result, the green case 50 is formed outside the first forming drum 32. Next, the green case 50 is transferred from the first forming drum 32 to the second forming drum 51 as shown in FIG. 5 by a transfer means (not shown) and fitted to the outside of the second forming drum 51.

  Here, the second forming drum 51 includes a rotatable main shaft 52 and a pair of bead lock bodies 53 supported by the main shaft 52 so as to be able to expand and contract, and to be movable in the axial direction. As described above, when the green case 50 is carried into the second forming drum 51, the pair of bead lock bodies 53 are expanded in diameter, and the bead cores 46 of the green case 50 are respectively supported from the radially inner side. Next, the bead lock body 53 is moved inward in the axial direction, and an internal pressure, for example, low-pressure air is supplied into the green case 50 between the bead cores 46 to bulge and deform the green case 50 into a substantially arcuate cross section.

  At this time, a cylindrical belt tread band 57 formed by winding a belt 55, a tread 56, etc. around the band drum (not shown) one after another is formed on the outside of the green case 50 in the radial direction by the band supply means 58. Is attached to the outside of the green case 50 to form a green tire. The green tire molded in this way is taken out from the second molding drum 51 and then carried into a vulcanization mold and vulcanized under high temperature and high pressure to become a pneumatic tire (vulcanized tire). .

Next, the operation of the first embodiment will be described.
When manufacturing a pneumatic tire using the manufacturing apparatus as described above, first, the band forming drum 14 in an expanded state is rotated, and a carcass ply or the like is supplied to the band forming drum 14 to surround it. Winding and cylindrical ply band 15 is formed. When the ply band 15 is formed in this way, after the conveying means 18 is moved to the vicinity of the band forming drum 14, the diameter of the band forming drum 14 is reduced, the ply band 15 is taken out from the band forming drum 14, and transferred. It is transferred to the conveying means 18 by the loading means or the operator's manual work.

  At this time, the upper support 19 of the conveying means 18 is inserted into the ply band 15, and the upper end portion of the ply band 15 is supported from the inside (lower side) by the upper support 19 of the conveying means 18. At the time of the above-mentioned transfer, the pressing body 28 is accommodated within the width of the upper support 19 because the gas is discharged from the inside and contracted, and as a result, the ply band 15 and the pressing body 28 Interference can be easily avoided.

  When the ply band 15 is transferred to the conveying means 18 as described above, the portion of the ply band 15 other than the upper end portion hangs down from the upper support 19 as indicated by a virtual line in FIG. The portion comes into contact with the upper surface 22a of the lower support 22 and is deformed flat, but when deformed in this way, a bent portion 16 having a small curvature is generated at both ends of the lower end portion (flat portion) of the ply band 15. Here, a large compressive strain is generated in such a bent portion 16, which causes wrinkles as described above. In particular, when it becomes necessary to temporarily store the ply band 15 in the conveying means 18 due to the convenience of the first forming drum 32, the degree becomes more prominent.

  However, in this embodiment, immediately after the ply band 15 is transferred to the transport means 18, gas is injected into the pressing body 28 to expand into an elliptical shape, and both side portions of the pressing body 28 are supported together. The body 19 is protruded laterally from both ends in the width direction. As a result, the middle portion in the vertical direction of the ply band 15 hanging from the upper support 19 is pushed outward in the width direction of the upper support 19 by the pressing body 28, so that the ply band 15 approaches a circular shape. As a result of the deformation, the aforementioned bent portion 16 disappears, and the generation of wrinkles due to the density of the carcass cord interval is effectively suppressed. Here, since the above-mentioned density becomes more prominent as the tire diameter increases, this embodiment is suitable for a large tire to be mounted on a large construction vehicle.

  Next, the conveying means 18 is moved to the vicinity of the first forming drum 32, and the ply band 15 supported by the conveying means 18 is conveyed to the first forming drum 32. Next, the gas is discharged from the pressing body 28 and contracted, and the pressing body 28 is accommodated within the width of the upper support 19. Next, the ply band 15 is taken out from the conveying means 18 by a transfer means or the like. At this time, since the pressing body 28 is within the width of the upper support body 19, the pressing body 28 and the ply band 15 interfere with each other. There is nothing. Next, after the ply band 15 is fitted to the outside of the first forming drum 32 in the reduced diameter state, the first forming drum 32 is expanded in diameter in the axial direction center of the ply band 15. The part 15a is supported from the inside.

  Next, the movable body 35 is moved inward in the axial direction to the inner limit so that the swinging blade 36 approaches the first forming drum 32, and then the holding body 37 is moved in the axial direction along with the support body 38. At this time, the holding body 37 is brought into sliding contact with the outer peripheral surface of the swing blade 36, so that the swing blade 36 swings synchronously radially inwardly with the outer end in the axial direction as the center. As a result, both axially outer side portions 15b of the ply band 15 are pushed inward in the radial direction by the swinging blades 36, and are narrowed (reduced in diameter) to a slightly smaller diameter than the bead core 46 while maintaining a substantially cylindrical shape.

  After the narrowing of the axially outer side portions 15b described above, the holding body 37 is further moved inward in the axial direction, and the bead core 46 with the filler 45 held in advance by the permanent magnet 44 is pressed against the stepped portion 15c. Deliver to 15. As a result, the bead core 46 is supplied and set to a predetermined position of the ply band 15, here, the step portion 15 c. Thereafter, the movable body 35, the holding body 37, and the support body 38 move outward in the axial direction, and a predetermined gap is formed between the first forming drum 32, the swing blade 36, and the holding body 37.

  Next, a high-pressure fluid is supplied into the folded bladder 39, and the folded bladder 39 is expanded in a substantially donut shape to enter the gap. Next, the holding body 37 and the support body 38 are moved inward in the axial direction, and the folding bladder 39 is pushed down inward in the axial direction by the holding body 37, so that the ply band 15 axially outer than the bead core 46 is moved around the bead core 46. Turn back to. Thereafter, the folded bladder 39 is contracted.

  Next, after the holding body 37 and the support body 38 are moved outward in the axial direction, side treads are supplied and wound around the outer sides of both ends of the ply band 15 in the axial direction while the first forming drum 32 is rotated. Is molded. Next, the green case 50 is transported to the second molding drum 51 by the transfer means and delivered to the second molding drum 51, and the bead lock body 53 is expanded in diameter, and the bead core 46 of the green case 50 is moved from the radially inner side. To support.

  Next, the bead lock body 53 is moved inward in the axial direction to bring the bead cores 46 of the green case 50 closer to each other, and an internal pressure is supplied into the green case 50 to cause the green case 50 to bulge and deform in a substantially arc shape in cross section. At this time, the belt-tread band 57 is carried in and attached to the outside in the radial direction of the green case 50 by the band supplying means 58 to form a green tire. The green tire molded in this way is taken out from the second molding drum 51 and then carried into a vulcanization mold and vulcanized under high temperature and high pressure to become a pneumatic tire (vulcanized tire). .

    FIG. 6 is a diagram showing Embodiment 2 of the present invention. Also in this embodiment, the pressing body 61 is provided between the upper support body 19 and the lower support body 22, but the support tool 62 that holds the upper end portion of the pressing body 61 has a rotating shaft 63 extending upward. Have. The pressing body 61 is rotatable about a vertical axis by the rotation shaft 63 being rotatably supported by a fixed block 64 fixed to the inner periphery of the upper support body 19 via a bearing 65. ing. Although the rotation angle of the pressing body 61 is 360 degrees in this embodiment, it may be 90 degrees or more.

  Further, the pressing body 61 has an elliptical annular shape extending in the horizontal direction like the pressing body 28, but the fluid passage 30 is omitted and the gas remains sealed inside. Further, since the length of the pressing body 61 (the length of the major axis of the ellipse) is larger than the width of the upper support 19, the pressing body 61 has a longitudinal direction around the vertical axis and the width of the upper support 19. When rotating until the direction matches, both ends in the longitudinal direction of the pressing body 61 protrude from the both side ends in the width direction of the upper support 19 to the side. As a result, the intermediate portion in the vertical direction of the ply band 15 hanging from the upper support 19 is pushed outward in the width direction by the pressing body 61, and the ply band 15 is deformed so as to approach a circular shape.

  On the other hand, since the width of the pressing body 61 (the length of the ellipse in the axial direction) is smaller than the width of the upper support body 19, the width direction of the pressing body 61 and the width direction of the upper support body 19 coincide with each other around the vertical axis. When it is rotated, the pressing body 61 is accommodated within the width of the upper support 19. Thereby, the pressing body 61 can easily avoid interference with the ply band 15 hanging from the upper support 19, and the band forming drum 14 of the ply band 15 is transferred from the band forming drum 14 to the conveying means 18. To the first molding drum 32 can be smoothed together.

    In the above-described embodiment, the pressing body 28 and the pressing body 61 at the time of expansion have an elliptical annular shape extending in the horizontal direction. However, in this invention, the pressing body has an elliptical columnar shape in which a cylinder is crushed in the vertical direction. Alternatively, it may have a substantially box shape with a bellows at the center and closed at both ends, and the bellows may extend in the horizontal direction by injecting fluid. Moreover, in this invention, it is good also as what combined both above-mentioned that a press body can be rotated to the surroundings of a vertical axis, and expand | swells and shrinks by injection | pouring of gas, and discharge | emission.

    Next, test examples will be described. In this test, 100 comparative tires using a ply band supported by a conveying means not provided with a pressing body and 100 implementation tires using a ply band supported by a conveying means provided with a pressing body were produced. did. Here, the size of each tire was 37.00R57.

  In each tire, the maximum amplitude and variation (maximum amplitude-minimum amplitude) of the undulation immediately below the bead core immediately after the axially outer side portions of the ply band were squeezed (reduced in diameter) were measured. The maximum amplitude was 123mm and the variation was 58mm, but the maximum amplitude was 67mm and the variation was reduced to 28mm in the implemented tires. The wrinkle generation rate for green tires was 87% for the comparative tires, but decreased to 3% for the implemented tires. Furthermore, the incidence of manufacturing defects such as overlap of ply cords under the bead in the vulcanized tires and steps at the ply ends was 8% for the comparative tires, but none (0%) for the implemented tires. . Thus, it was confirmed that the generation of wrinkles and manufacturing defects can be reduced by reducing the maximum amplitude of undulation.

  The present invention can be applied to the industrial field of manufacturing a pneumatic tire, particularly a large pneumatic tire to be mounted on a large construction vehicle or the like.

It is a partially broken front view which shows Embodiment 1 of this invention. It is a left view of a conveyance means. It is front sectional drawing of the 1st shaping | molding drum vicinity. It is front sectional drawing explaining the folded state of a ply band. It is front sectional drawing of the 2nd shaping | molding drum vicinity. It is a side view similar to FIG. 2 which shows Embodiment 2 of this invention.

Explanation of symbols

14 ... Band molding drum 15 ... Ply band
15b ... Axial outer part 15c ... Step part
18 ... Conveying means 19 ... Upper support
19a ... Upper surface 21 ... Roller
22 ... Lower support 22a ... Upper surface
25 ... Connected body 28 ... Pressing body
32 ... First molding drum 41 ... Narrowing means
46 ... Bead core 47 ... Bead setting means
48 ... Return means

Claims (6)

    A band forming drum that forms a cylindrical ply band by winding at least a carcass ply around the periphery, a conveying unit that conveys the ply band from the band forming drum to the first forming drum, and the first forming drum. Narrowing means for narrowing both outer sides of the ply band in the axial direction, bead setting means for setting the bead core in the stepped portion of the ply band formed by the narrowing, and a folding means for folding the ply band axially outside the bead core around the bead core In the pneumatic tire manufacturing apparatus, the conveying means is inserted in the ply band in the axial direction, the upper surface is gently curved upward and the upper end of the ply band is The upper support that is supported from the inside by the upper surface, and installed immediately below the support, A flat lower support whose distance from the upper surface of the upper support to the upper end of the upper support is substantially equal to the diameter of the ply band, and a connecting body that extends in the vertical direction and connects the upper and lower supports to each other. Pneumatic tire manufacturing equipment.     The pneumatic tire manufacturing apparatus according to claim 1, wherein a plurality of free-rotating rollers are supported by the upper support, and a part of the rollers protrudes from the upper surface of the upper support.     Between the upper support body and the lower support body, a pressure body that can be expanded and contracted by gas injection and discharge and supported by the upper support body is provided, and both ends of the pressure body are expanded by expanding the pressure body. 3. The air according to claim 1, wherein the pressing portion is accommodated within the width of the upper support by causing the portion to protrude laterally from both ends in the width direction of the upper support, and contracting the pressing body. Manufacturing equipment for entering tires.     Between the upper support and the lower support, there is provided a pressing body that is rotatable about a vertical axis and that is supported by the upper support and extends in the horizontal direction. It is larger than the width, and both ends in the longitudinal direction can be protruded laterally from both ends in the width direction of the upper support, while the width is smaller than the width of the upper support, and the pressing body is within the width of the upper support. The pneumatic tire manufacturing apparatus according to claim 1, wherein the pneumatic tire manufacturing apparatus can be stored in the tire.     The pneumatic tire manufacturing apparatus according to claim 3 or 4, wherein the pressing body has an elliptical annular shape in which a cylindrical shape is crushed in the vertical direction.     A step of forming a cylindrical ply band by winding at least a carcass ply around the band forming drum, a step of transferring the ply band from the band forming drum to the first forming drum by a transfer means, and a transfer to the first forming drum A step of narrowing both axially outer side portions of the ply band formed by the narrowing means, a step of setting the bead core to the stepped portion of the ply band formed by the narrowing by the bead setting means, and a ply band outside the bead core in the axial direction. A pneumatic tire manufacturing method including a step of folding back around a bead core by a folding means, wherein the conveying means has an upper support whose upper surface is gently curved upward and an upper support from the upper surface. A flat lower support whose distance to the upper end of the body is substantially equal to the diameter of the ply band; When the upper and lower support members are connected to each other and extend in the vertical direction, the upper support member is inserted into the ply band in the axial direction, and the upper end portion of the ply band is connected to the upper support member. A method for producing a pneumatic tire, wherein the pneumatic tire is supported from the inside by an upper surface.

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