JP4886840B2 - Raw tire forming method and raw tire forming apparatus - Google Patents

Description

  The present invention relates to a green tire forming method and a green tire forming apparatus for efficiently and accurately forming a tire of a so-called bead wind structure in which both ends of a carcass ply are turned around a bead core and locked. .

  For example, Patent Document 1 below proposes a bead forming apparatus for a tire having a bead wind structure. In this bead forming apparatus, as shown in FIG. 17, a sheet-like carcass ply a is wound around the outer circumferential surface to form a cylindrical carcass cylinder, and is externally inserted into the carcass cylinder. It comprises a bead core support means B having a lock ring B1 capable of expanding and contracting to support the bead core b by increasing the diameter, and a winding means C having a ply winding ring C1 movable inward and outward in the axial direction.

JP 2006-103198 A JP 2007-320196 A

  In this bead forming apparatus, an outer piece B1a is provided on the lock ring B1, and the protruding portion a1 from the bead core b is raised outward in the radial direction simultaneously with the fixation of the bead core b. In this case, however, strictly speaking, the outer piece B1a first contacts the carcass ply a, and the rising of the protruding portion a1 starts prior to fixing. For this reason, there is a problem that the starting position and the carcass cord path between the bead cores are unstable.

  On the other hand, as a method of jointing (joining) the circumferential ends of the carcass ply a that is wound once, generally, as shown in FIGS. 18A and 18B, the circumferential end of the carcass ply a is used. An overlap joint J1 that overlaps and joins the portions ae or a zipper joint J2 that joins the end edges ae1 of each end ae abutting each other as shown in Patent Document 2 is known. However, in the case of the overlap joint J1, the thickness and rigidity are doubled at the overlapping portion f between the end portions ae, so that it is difficult to wind the carcass tube around the bead core b. Therefore, in the bead wind structure, the zipper joint J2 Is preferably adopted.

  On the other hand, when the zipper joint J2 is employed in the bead forming device, the lower piece g that receives the radially inner side of the end ae is axially centered on both the former A and the lock ring B1 of the bead core support means B. It is necessary to form a groove-shaped notch that passes in the direction. The reason is that in the bead forming apparatus, the bead core support means B is arranged substantially integrally with the former A without moving relative to the former A in the axial direction.

  However, when the notch portion is provided in the lock ring B1, the carcass ply a is sandwiched and fixed between the bead core b and the protruding portion a1 of the carcass ply a is radiused at the notch portion. Cannot stand up outward. For this reason, at the position of the notch portion, problems such as a decrease in winding accuracy and deformation of the winding portion also occur.

  Therefore, the present invention can stabilize the rising position at the protruding portion of the carcass ply and the carcass cord path between the bead cores, and can employ a zipper joint without providing a notch in the lock ring. An object of the present invention is to provide a green tire forming method and a green tire forming apparatus capable of efficiently and efficiently winding a carcass ply around a bead core in a structure.

In order to solve the above-mentioned problem, the invention of claim 1 of the present application is such that a sheet-like carcass ply is protruded from both ends of the central drum on the outer peripheral surface of the central drum capable of expanding and contracting. A carcass tube forming step having a winding step that makes a round turn in a cylindrical shape, and a joining step in which circumferential ends of the carcass ply wound around the round are brought into contact with each other and zippered together,
The side drums arranged on both sides in the axial direction of the central drum are arranged close to the central drum from the separated state in which the side drums are spaced apart from the outer end portion by a distance D in the axial direction. A side drum lateral movement step for laterally moving inward in the axial direction to the proximity state of receiving the outer end portion of
A bead lock that holds the externally inserted bead core with the outer end portion sandwiched by expanding the diameter of a lock ring that can be expanded and contracted provided on the side drum after the bead core is extrapolated to the outer end portion. Process,
A carcass winding step of winding a protruding portion of the carcass tube outside in the axial direction from the bead core around the bead core;
The carcass winding step includes
A ply turn-up ring that can be expanded in diameter on the side drum on the outer side in the axial direction of the lock ring is expanded to raise the protruding portion toward the outer surface of the bead core and to stand outward in the radial direction. Raising step,
In a state where the ply turn-up ring is expanded, the ply turn-up ring is moved laterally inward in the axial direction, so that it is located radially outside the outer peripheral surface of the bead core. A tilting step of tilting the overhang portion toward the outer peripheral surface of the bead core;
And a pressing step of pressing the overhanging protruding portion against the outer peripheral surface of the bead core using a stitch roller.

  In the invention of claim 2, the stitch roller is composed of a concavo-convex roller having a concavo-convex surface in which the roller surface repeats concavo-convex in the circumferential direction and a smooth roller having a smooth surface on the roller surface. It is characterized in that the pressing is performed by an uneven roller.

  In the invention of claim 3, the carcass winding step includes a wrapping step in which the portion pressed by the pressing step is fixed to the outer peripheral surface of the bead core with a wrapping wire wound outside in the radial direction. It is a feature.

The invention according to claim 4 is an invention of a green tire forming apparatus, which is rotatably held on the drum central shaft portion, and a sheet-like carcass ply is wound around the outer peripheral surface to form a cylindrical carcass cylinder. A central drum capable of expanding and contracting,
From a proximity state in which the outer end portion of the carcass tube is disposed on both sides in the axial direction of the central drum and protrudes outward in the axial direction from the central drum in the vicinity of the central drum, the axial direction from the outer end portion A side drum that can move inward and outward in the axial direction between the outer side and a separated state that is separated by a distance D;
In the first slide case, the side drum is held on the drum central shaft portion so as to be integrally rotatable with the central drum, and can move in and out in the axial direction between the proximity state and the separation state.
A bead lock means having a lock ring capable of expanding and contracting to hold a bead core that is extrapolated to the outer end portion by expanding the diameter;
A winding means that is arranged on the outer side in the axial direction of the bead lock means and winds a protruding portion of the carcass tube that is axially outer than the bead core, around the bead core;
The winding means is configured such that the protruding portion of the bead core is formed by expanding the diameter of the bead core on a second slide case that is disposed on the first slide case so as to be movable inward and outward in the axial direction relative to the first slide case. It has a ply turn-up ring that can be expanded and contracted to rise radially outward toward the outer surface,
In addition, the ply turn-up ring has an outer peripheral surface of the bead core in the rising portion by the relative movement of the second slide case in the axial direction in a state in which the ply turn-up ring is expanded. The overhanging portion on the radially outer side is tilted toward the outer peripheral surface of the bead core.

  In the present invention, as described above, side drums having lock rings capable of expanding and contracting are arranged on both sides in the axial direction of the central drum so as to be movable inward and outward in the axial direction. Therefore, when the side drum is in the separated state, the zipper joint device can be inserted from this separated portion. That is, it is not necessary to form a notch through which the lower frame body passes through the lock ring, and it becomes possible to perform a zipper joint by forming the notch only in the center drum.

  The lock ring is enlarged in diameter and fixed with the carcass ply sandwiched between the bead core and the lock ring, and then the ply turn-up ring is enlarged to raise the protruding portion of the carcass ply. Accordingly, the carcass ply rising position and the carcass cord path between the bead cores can be stabilized, and the carcass ply is wound around the bead core in the bead wind structure in combination with the elimination of the notch in the lock ring. Can be performed with high accuracy and efficiency. Further, since the bead lock means and the winding means are provided in one slide case, the cost and size of the apparatus can be reduced and the winding accuracy can be reduced as compared with the apparatus of FIG. 17 provided separately. It can contribute to improvement and shortening of the process time from the bead lock process to the carcass winding process.

It is sectional drawing which shows one Embodiment of the bead part in the tire of the bead wind structure formed using the formation method of the raw tire of this invention. It is meridional sectional drawing which shows the formation apparatus of the raw tire for enforcing the formation method of a raw tire. It is meridional sectional drawing which expands and shows the center drum. It is meridional sectional drawing which expands and shows the principal part of the side drum in a reduced diameter state. It is meridional sectional drawing which expands and shows the principal part of the side drum in a diameter-expanded state. It is sectional drawing of a direction perpendicular to the axial center direction which shows the diameter expansion state of a center drum, and a diameter-reduced body. It is sectional drawing of the diameter direction of an axial center direction which shows the diameter expansion state of a lock ring, and a diameter-reduced body. FIG. 6 is a cross-sectional view in a direction perpendicular to the axial direction showing a diameter-expanded state of the ply turn-up ring and a reduced diameter body. (A), (B) is the front view which shows the slide ring of a winding means, and meridional sectional drawing. (A)-(D) are sectional drawings which show operation | movement of the bead lock means and winding means in a side drum with time. (A) and (B) are the conceptual diagrams explaining a carcass cylinder formation process. It is a conceptual diagram explaining a side drum horizontal movement process. (A), (B) is a conceptual diagram explaining a bead lock process. (A) and (B) are the conceptual diagrams explaining the start-up step in the carcass winding process, and the fall-down step. It is a conceptual diagram explaining the pressing step in a carcass winding process. It is a conceptual diagram explaining the lapping step in a carcass winding process. It is sectional drawing which shows the conventional bead shaping | molding apparatus. (A), (B) is a conceptual diagram explaining the method of joining between the edge parts of the circumferential direction of a carcass ply.

  Hereinafter, embodiments of the present invention will be described in detail. FIG. 1 is a meridional section of a bead portion 4 when the tire 1 having a bead wind structure is a heavy load radial tire, and the tire 1 passes through a sidewall portion 3 from a tread portion having a ground contact surface, and the bead portion 4. The carcass 6 reaching the bead core 5 is provided at least, and a well-known belt layer for reinforcing the tread is disposed on the outer side in the radial direction of the carcass 6 and on the inner side of the tread portion.

  The carcass 6 is composed of one carcass ply 6A in which a carcass cord (steel cord) arranged in parallel is covered with a topping rubber, and in the case of a radial tire, the carcass cord is arranged in the tire circumferential direction. It is arranged at an angle of 75 to 90 °.

  The carcass ply 6A circulates around the bead core 5 from the inner side to the outer side in the tire axial direction on both sides of the toroidal carcass main body 6a spanned between the bead cores 5 and 5, and the tip E of the carcass ply 6A A series of carcass winding portions 6b that end close to the portion 6a are provided.

  The bead core 5 includes a core body 5A formed by winding, for example, steel bead wires in multiple stages and multiple rows, and in this example, a thin coating layer made of a rubberized cloth or a rubber sheet for preventing the bead wires from being loosened around the core body 5A. The thing provided with 5B is illustrated. The bead core 5 includes a core inner peripheral surface SL which is a radial inner peripheral surface facing the rim sheet Js surface of the rim J, a core outer peripheral surface SU which is a radial outer peripheral surface parallel to the core inner peripheral surface SL, A core outer surface SO that is an outer surface in the axial direction that connects between the outer peripheral edges P2 and P4 of the tire axial direction between the circumferential surface SL and the core outer peripheral surface SU, and an inner surface in the axial direction that connects between the inner edges P1 and P5 in the tire axial direction. A cross-sectional polygonal shape having a peripheral surface made of the core inner surface SI is formed. In particular, in this example, the core outer side surface SO and the core inner side surface SI are respectively inclined to the upper inclined surfaces SOa, SIa, which are inclined from the tops P3, P6 of the respective intermediate heights toward the core outer peripheral surface side and the core inner peripheral surface side. An example of a hexagonal cross-section formed by the inclined surfaces SOb and SIb is illustrated, and the fitting force with the rim is enhanced over a wide range by the core inner peripheral surface SL being substantially parallel to the rim sheet Js. In this example, the rim J is a tubeless 15 ° taper rim. Therefore, the core inner circumferential surface SL is inclined at an angle of approximately 15 ° with respect to the tire axial line.

  The carcass winding portion 6b includes a main portion 8 along the core inner surface SI, the core inner peripheral surface SL, and the core outer surface SO of the bead core 5, and a sub-surface that is connected to the main portion 8 and faces the core outer peripheral surface SU. Part 9. In this example, a wrapping wire 10 is spirally wound on the sub-portion 9, and the sub-portion 9 is pressed against the core outer peripheral surface SU and restrained. As a result, the carcass cord is bent back and the following problems resulting therefrom, for example, an air pocket is generated between the sub-portion 9 and the bead core 5 during vulcanization molding, and the durability is deteriorated. This prevents problems such as the occurrence of blow-through phenomenon and cord looseness.

  Next, as shown in FIG. 2, the forming device 11 that forms the green tire of the pneumatic tire includes a central drum 13 that is rotatably held by the drum central shaft portion 12, and an axial direction of the central drum 13. The central drum 13 includes a side drum 14 disposed on both sides, and the central drum 13 forms a cylindrical carcass cylinder 15 by winding the sheet-like carcass ply 6 </ b> A on its outer peripheral surface. Further, the side drum 14 is close to the central drum 13 and closes to the outer side in the axial direction from the outer end portion 15E from a proximity state Y1a that receives the outer end portion 15E of the carcass tube 15 protruding outward from the central drum 13 in the axial direction. Can move in and out of the axial direction up to a separated state Y1b separated by a distance D.

  The drum central shaft portion 12 includes a spindle main body 12A that is driven by a motor, and a cylindrical sleeve 12B that is concentrically held by the spindle main body via a bearing. The support shaft main body 12A and the sleeve 12B are connected to each other by a clutch mechanism (not shown) so as to be switched between a connected state in which the support shaft main body 12A can rotate integrally and a non-connected state in which only the support shaft main body 12A can rotate independently. The The spindle main body 12A is formed with a left screw part 12A1 and a right screw part 12A2 on both sides of the former equator position C0, and a left screw thread in the gap between the spindle main body 12A and the sleeve 12B. Nut fittings 16 and 16 are arranged to be screwed with the portion 12A1 and the right screw portion 12A2, respectively. The nut member 16 and the side drum 14 are integrally connected via a connecting member 18 formed in the sleeve 12B and passing through a guide hole 17 extending in the axial direction.

  Accordingly, in the non-connected state, only the support shaft body 12A is rotated by motor driving, and the pair of side drums 14 and 14 are centered on the former equator position C0 via the nut metal fitting 16 and the connection metal fitting 18. It can be moved in and out of the axial direction between the proximity state Y1a and the separation state Y1b. In the connected state, the side drum 14 can rotate together with the spindle body 12A and the sleeve 12B at a predetermined movement position.

  The central drum 13 includes a drum portion 13A composed of a plurality of drum segments 20 divided in the circumferential direction, and first expansion / contraction means 21 for moving each drum segment 20 inward and outward in the radial direction. As shown in FIG. 6, the drum portion 13 </ b> A has a reduced diameter state Pr in which each drum segment 20 moves inward in the radial direction and the outer circumferential ends 20 e approach each other to form a closed cylindrical body. And a radially expanded state Pe that moves radially outward and the circumferential outer ends 20e are separated from each other. In this example, the carcass ply 6A is wound once on the outer peripheral surface of the drum portion 13A in the reduced diameter state Pr.

  Further, the drum portion 13A has a notch portion h through which a frame body g of a known zipper joint device 55 passes at a position where the circumferential edges of the carcass ply 6A are zippered together. It is formed over.

  Further, as shown in FIG. 3, the first expansion / contraction means 21 includes a slide fitting 22 arranged concentrically with the sleeve 12B so as to be movable in the axial direction, and each of the drum segments 20 at a radially outer end portion. And a plurality of radially moving pieces 23 that can move in the radial direction by engaging with the slide fitting 22.

  In this example, a holding cylinder 24 is integrally fixed to the sleeve 12 </ b> B, and the slide fitting 22 is extrapolated to the holding cylinder 24. The slide fitting 22 is formed of a cone-shaped ring body whose outer peripheral surface is a tapered surface portion 22S inclined inward in the radial direction toward one side in the axial direction. For example, the axial center is formed by a rod 25 connected to a cylinder or the like. Can slide in the direction. The slide fitting 22 and the holding cylinder 24 are prevented from rotating by using, for example, a keyway. Further, the holding cylinder 24 is provided with a disk-shaped side wall portion 24A that rises in the radial direction from the side end on one side in the axial direction, and a side surface on the other side in the axial direction has, for example, a guide groove or the like. A plurality of guide portions 24A1 are radially formed in the radial direction.

  The radial moving piece 23 has a side end on one side in the axial direction guided in the radial direction by the guide portion 24A1, and the radially inner end portion and the tapered surface portion 22S of the slide fitting 22 are In the example, it engages via the linear bearing 26 along the inclination of the taper surface part 22S. Therefore, in the first expansion / contraction means 21, each moving piece 23 can be pushed up and moved radially outward together with the drum segment 20 by sliding the slide fitting 22 in one axial direction of the slide fitting 22.

  Next, as shown in FIG. 4, the side drum 14 has a bead core 5 that is externally inserted into the outer end portion 15 </ b> E of the carcass cylinder 15 in a first slide case 27 held by the drum central shaft portion 12. A bead lock means 29 having a lock ring 28 that can be expanded and contracted and held across the outer end portion 15E, and an expansion / reduction that winds the protruding portion 15E1 of the carcass cylinder 15 axially outside the bead core 5 around the bead core 5. A winding means 31 having a ply turn-up ring 30 capable of diameter is provided.

  The first slide case 27 includes a cylindrical portion 27a that is slidably fitted on the sleeve 12B, and an axially inner end side, an outer end side, and an intermediate portion of the cylindrical portion 27a on the radially outer side. The side walls 27i, 27o and 27m are provided inside, outside and inside. Between the inner and inner side wall portions 27i and 27m, a cylindrical slide ring receiving space Ha concentric with the cylindrical portion 27a and extending in the axial direction, and an axially outer end of the slide ring receiving space Ha. A moving piece storage space Hb that extends continuously outward in the radial direction is formed. The first slide case 27 can rotate integrally with the central drum 13 by fixing the cylindrical portion 27a to the coupling metal 18, and is axially extended from the proximity state Y1a to the separation state Y1b. Can move on.

  Next, the bead lock means 29 includes the lock ring 28 using a plurality of lock segments 32 divided in the circumferential direction, and second expansion / contraction means 33 for expanding and contracting the lock ring 28. As shown in FIG. 7, the lock ring 28 moves radially outward from a reduced diameter state Pr in which each lock segment 32 moves radially inward and brings the outer circumferential ends 32e close to each other. In the expanded diameter state Pe, the bead core 5 can be held with the outer end portion 15E sandwiched therebetween, and in the reduced diameter condition Pr. The held bead core 5 is released.

  The lock ring 28 includes a ring-shaped core receiving portion 34 (shown in FIGS. 4 and 5) that is arranged at the outer end in the radial direction and extends continuously in the circumferential direction. The core receiving portion 34 is made of a rubber elastic material, and can expand and contract following the expansion / contraction diameter. A core receiving surface 34S that receives the core inner peripheral surface SL of the bead core 5 is formed on the outer peripheral surface thereof.

  Next, the second expansion / contraction means 33 is disposed in the slide ring housing space Ha and is disposed in the moving piece housing space Hb and a piston-like slide ring 35 that can slide in the axial direction. A plurality of radially moving pieces 36 are provided that can move inward and outward in the radial direction and have each lock segment 32 attached to the radially outer end.

  In this example, the slide ring 35 is formed of a cone-shaped ring body having an outer end portion in the axial center direction as a tapered surface portion 37 inclined inward in the radial direction toward the outer side in the axial center direction. The slide ring 35 can slide in the axial direction when compressed air flows in from the air flow path 38 that passes through the inner side wall portion 27i and communicates with the slide ring housing space Ha. The slide ring 35 and the cylindrical portion 27a are prevented from rotating by using, for example, a key groove.

  Further, the side surface in the axial direction of the radially moving piece 36 is guided in the radial direction by a guide portion Hb1 such as a guide groove provided on the inner wall surface of the moving piece receiving space Hb, and the radially inner end portion thereof. In this example, the taper surface portion 37 of the slide ring 35 is engaged via a roller 39 pivotally attached to the radially inner end portion of the radial movement piece 36. Therefore, in the second expansion / contraction means 33, each moving piece 36 can be pushed up and moved radially outward together with the lock segment 32 by sliding the slide ring 35 outward in the axial direction.

  Next, the winding means 31 includes a second slide case 40 held by the first slide case 27 as shown in FIG. A ply turn-up ring 30 capable of expanding and contracting the protruding portion 15E1 radially outward toward the core outer surface SO of the bead core 5 and a third expanding / contracting means 42 for expanding and contracting the ply turn-up ring 30 are provided. Arranged.

  The second slide case 40 includes a cylindrical barrel portion 40a that is slidably fitted on the cylindrical portion 27a between the inner side wall portions 27m and 27o, and an axial center of the barrel portion 40a. Outer side walls 40i, 40o are provided on the inner end side and the outer end side in the radial direction. Between the inner and outer side wall portions 40i and 40o, a cylindrical slide ring accommodating space Ja concentric with the barrel portion 40a in the axial direction and an inner end in the axial direction of the slide ring accommodating space Ja. A moving piece storage space Jb that extends continuously outward in the radial direction is formed. In the second slide case 40, the outer side wall 40i is brought into contact with the outer side wall 27o from an advanced state Y2a (shown in FIG. 5) in which the inner side wall 40i contacts the inner side wall 27m. The first slide case 27 can move in and out of the axial direction relative to the retracted state Y2b (shown in FIG. 4) in contact with the first slide case 27. In this embodiment, the second slide case 40 is operated by a rod 43 that protrudes from the outer side wall 40o and extends through the outer side wall 27o and extends rearward in the axial direction. 43 is actuated by a piston 44 which is arranged in a cylinder chamber 70 provided in the outer side wall 27o and can move in the axial direction. The piston 44 and the second slide case 40 can slide in the axial direction when compressed air flows into the cylinder chamber 70 from the air flow path 71.

  The ply turn-up ring 30 is composed of a plurality of segments 45 divided in the circumferential direction. The segment 45 includes a first segment 45A having a large circumferential width, as shown in FIG. The first segment 45A has a small direction width and is composed of second segments 45B arranged alternately in the circumferential direction. Both end surfaces 45Ae in the circumferential direction of the first segment 45A are formed as inwardly inclined surfaces that incline in the direction of decreasing the circumferential width inward in the radial direction. Further, both end surfaces 45Be in the circumferential direction of the second segment 45B are formed as outwardly inclined surfaces that are inclined in the direction of increasing the circumferential width inward in the radial direction.

  In the expanded diameter state Re, the first and second segments 45A and 45B are arranged side by side in the circumferential direction, and the circumferential end faces 45Ae and 45Be are in contact with each other. The segments 45A and 45B cooperate with each other to form a substantially continuous cylindrical body. In the reduced diameter state Rr, the second segment 45B moves backward inward in the radial direction with respect to the first segment 45A, whereby the ply turn-up ring 30 can be reduced in diameter.

  The third expanding / contracting means 42 is disposed in the slide ring receiving space Ja and is slidable in the axial direction, and is disposed in the moving piece receiving space Jb. It comprises a plurality of radially moving pieces 47 that can move inward and outward and have each segment 45 attached to the radially outer end.

  The slide ring 46 is a cone-shaped ring body whose inner end in the axial direction is a tapered surface portion 48 that is inclined inward in the radial direction toward the inner side in the axial direction, and is formed in the slide ring accommodating space Ja. When compressed air flows in from the air flow path 49 that communicates, it can slide in the axial direction. The slide ring 46 and the body 40a are prevented from rotating by using, for example, a keyway.

  Further, as shown in FIGS. 9A and 9B, the tapered surface portion 48 is formed of first and second tapered surface portions 48A and 48B which are different in inclination and are alternately arranged in the circumferential direction. . In the present example, the second tapered surface portion 48B is composed of a single inclined surface having a constant gradient. Further, the first tapered surface portion 48A passes through the outer side in the radial direction than the second tapered surface portion 48B, and in this example, the inner inclined surface portion 48A1 on the inner side in the axial direction extends with substantially the same gradient as the second tapered surface portion 48B. An outer inclined surface portion 48A2 on the outer side in the axial direction that is flush with the second tapered surface portion 48B, a gentle inclination than the second tapered surface portion 48B, and the inner inclined surface portion 48A1 and the outer inclined surface portion 48A2. It is comprised from the intermediate | middle inclined surface part 48A3 to join. As the first tapered surface portion 48A, for example, the inner inclined surface portion 48A1 can be formed with a different slope from the second tapered surface portion 48B, or the intermediate inclined surface portion 48A3 can be formed as a horizontal surface. It can be modified to various aspects.

  The radial moving piece 47 is formed by a first moving piece 47A having the first segment 45A attached to the radially outer end thereof and a second moving piece 47B having the second segment 45B attached. Is done. Each of the moving pieces 47A, 47B has substantially the same configuration, and the side surface in the axial center direction is guided in the radial direction by a guide portion Jb1 such as a guide groove provided on the inner wall surface of the moving piece housing space Jb. In this example, the radially inner end portion and the tapered surface portion 48 of the slide ring 46 are engaged via a roller 50 pivotally attached to the radially inner end portion of each radial moving piece 47. Accordingly, in the third expansion / contraction means 42, the rollers 50 of the first and second moving pieces 47A and 47B roll while contacting the first and second tapered surface portions 48A and 48B, respectively. As the slide ring 46 moves inward in the axial direction, the first and second segments 20A and 20B can be pushed up and moved radially outward.

  At this time, when the roller 50 of the first moving piece 47A is in contact (engagement) with the inner inclined surface portion 48A1, the first segment 45A is fixed radially outward from the second segment 45B. While keeping the distance, that is, moving forward in the radial direction while leading a certain distance. Further, when in contact (engagement) with the middle inclined surface portion 48A3, the first segment 45A moves outward in the radial direction while reducing the distance from the second segment 45B. At the radially outer end position j of the middle inclined surface portion 48A3, the distance becomes 0, the second segment 45B catches up with the first segment 45A, and the first and second segments 45A, 45B are surrounded. The diameter-expanded state Re can be arranged side by side in the direction.

  As shown in FIG. 4, the outer diameter of the drum portion 13A in the reduced diameter state Pr, the outer diameter of the lock ring 28 in the reduced diameter state Qr, and the outer diameter of the ply turn-up ring 30 in the reduced diameter state Rr. Are substantially equal to each other. Further, as shown in FIG. 5, the outer diameter of the drum portion 13A in the expanded state Pe and the outer diameter of the lock ring 28 in the expanded state Qe are substantially equal to each other, and the expansion of the ply turn-up ring 30 is increased. The outer diameter in the diameter state Re is set larger than them.

  10A to 10D show the operation of the bead lock means 29 and the winding means 31 in the side drum 14 over time.

  Next, a forming method for forming a green tire for a bead wind structure tire using the forming apparatus 11 will be described. This forming method includes a carcass cylinder forming step T1 for forming the carcass cylinder 15, a side drum lateral movement process T2 for laterally moving the side drum 14 in the axial direction, a bead lock process T3 for holding the bead core 5, and a carcass cylinder 15 A carcass winding step T4 for winding the protruding portion 15E1 around the bead core 5 is configured.

  In the carcass tube forming step T1, as shown in FIGS. 11A and 11B, in the separated state Y1b of the side drum 14, the carcass ply 6A is disposed on the outer peripheral surface of the center drum 13 both axially outside. A winding step T1a for projecting the end portion 15E from both ends of the central drum 13 and making a round turn in a cylindrical shape, and a joining step T1b for making a zipper joint by abutting the circumferential edges of the carcass ply 6A wound around the end Have

  In the winding step T1a, the carcass ply 6A supplied from the ply servicer using the belt conveyor 54 is pressed against the central drum 13, whereby the carcass ply 6A is wound together with the rotation of the central drum 13. In addition, centering with the carcass ply 6A and the center drum 13 to carry in is performed by adjusting the position of the belt conveyor 54 to an axial center direction. In the joining step T1b, the side drum 14 in the separated state Y1b separates the distance D from the carcass ply 6A, so that the zipper joint device 55 can be inserted from the separated portion of the distance D.

  Next, in the side drum lateral movement step T2, as shown in FIG. 12, the side drum 14 is laterally moved in the axial direction from the separated state Y1b to the close state Y1a, and the outer end portion 15E of the carcass cylinder 15 is radiused. Receive from the inside.

  Next, in the bead lock process T3, as shown in FIGS. 13A and 13B, after the bead core 5 is extrapolated from the one end side of the forming apparatus 11 to the outer end portion 15E, the side drum 14 By expanding the diameter of the lock ring 28 from the reduced diameter state Qr to the expanded diameter state Qe, the bead core 5 is held across the outer end portion 15E. At this time, the diameter of the drum portion 13 </ b> A is expanded simultaneously with the lock ring 28. Thereby, the bending of the carcass ply 6A between the bead cores 5 and 5 can be suppressed, and the fluctuation of the carcass cord path accompanying the bead lock can be prevented.

  Next, the carcass winding step T4 includes a startup step T4a, a tilting step T4b, and a pressing step T4c. In the start-up step T4a, as shown in FIG. 14A, the ply turn-up ring 30 is expanded from the reduced diameter state Rr to the enlarged diameter state Re, so that the protruding portion 15E1 from the bead core 5 is removed. 5 is raised radially outward toward the core outer surface SO.

  In the inclining step T4b, as shown in FIG. 14B, the ply turn-up ring 30 in the expanded diameter state Re is laterally moved inward in the axial direction from the retracted state Y2b to the advanced state Y2a. As a result, the protruding portion 15E1a radially outward from the core outer peripheral surface SU of the bead core 5 in the raised portion (corresponding to the protruding portion 15E1) is tilted toward the core outer peripheral surface SU of the bead core. A first winding portion that is inclined along the upper inclined surface SOa of the core outer surface SO at the inner end in the axial center direction of the ply turn-up ring 30 and presses the protruding portion 15E1a against the upper inclined surface SOa. 30a and a second winding portion 30b that protrudes inward in the tire axial direction with a small length from the first winding portion 30a. The second winding portion 30b protrudes inward in the axial center direction from the top portion P3 of the bead core 5 and separates a distance corresponding to the thickness of the carcass ply 6A from the top portion P3 in the radial direction outside.

  In the pressing step T4c, the overhanging portion 15E1a is pressed against the core outer peripheral surface SU by using the stitch roller 56 with the overhanging portion 15E1a in the collapsed state as shown in FIG. Thus, the overhang portion 15E1a is molded. In this example, the stitch roller 56 includes a concave / convex roller 56A having a concave / convex surface in which the roller surface repeats irregularities in the circumferential direction, and a smooth roller 56B having a smooth surface as the roller surface. The pressing is performed by the uneven roller 56A. As described above, by using the uneven roller 56A first, the protruding portion 15E1a separated from the core outer peripheral surface SU can be pressed against the core outer peripheral surface SU. Therefore, it is preferable that the uneven roller 56A has a serrated uneven surface. The smooth roller 56B smoothes and finishes the uneven roller marks generated by the uneven roller 56A.

  In the carcass winding step T4, as shown in FIG. 16, the overhanging portion 15E1a pressed in the pressing step T4c is wound around the core outer peripheral surface SU with a wrapping wire 10 spirally wound outside in the radial direction. Including a wrapping step T4d. The wrapping wire 10 is wound in a collapsed state by the ply turn-up ring 30.

  Then, the carcass tube 15 in which the protruding portion 15E1 is wound around the bead core 5 and restrained by the wrapping wire 10 is formed by the diameter reduction of the drum portion 13A, the lock ring 28, and the ply turn-up ring 30. After being removed from 11, the tire is joined to the tread ring by a shaping process or the like as in the conventional case to form a raw tire.

  As mentioned above, although especially preferable embodiment of this invention was explained in full detail, this invention is not limited to embodiment of illustration, It can deform | transform and implement in a various aspect.

5 Bead core 6A Carcass ply 10 Lapping wire 12 Drum center shaft portion 13 Central drum 14 Side drum 15 Carcass cylinder 15E Outer end portion 15E1 Overhang portion 15E1a Overhang portion 27 First slide case 28 Lock ring 29 Bead lock means 30 Ply turn up ring 31 Winding means 40 Second slide case 56 Stitch roller 56A Concavity and convexity roller 56B Smooth roller SU Outside surface T1 of bead core T1 Carcass tube forming step T1a Winding step T1b Joining step T2 Side drum lateral movement step T3 Bead lock step T4 Carcass winding step T4a Startup step T4b Tilting step T4c Pressing step T4d Lapping step Y1b Separation state Y1a Proximity state

Claims (4)

A winding step of winding a sheet-like carcass ply on the outer peripheral surface of the central drum capable of expanding and contracting in a cylindrical shape with both axial end portions protruding from both ends of the central drum. A step of forming a carcass cylinder having a joining step in which the circumferential edges of the carcass ply are abutted against each other and zippered together,
The side drums arranged on both sides in the axial direction of the central drum are arranged close to the central drum from the separated state in which the side drums are spaced apart from the outer end portion by a distance D in the axial direction. A side drum lateral movement step for laterally moving inward in the axial direction to the proximity state of receiving the outer end portion of
A bead lock that holds the externally inserted bead core with the outer end portion sandwiched by expanding the diameter of a lock ring that can be expanded and contracted provided on the side drum after the bead core is extrapolated to the outer end portion. Process,
A carcass winding step of winding a protruding portion of the carcass tube outside in the axial direction from the bead core around the bead core;
The carcass winding step includes
A ply turn-up ring that can be expanded in diameter on the side drum on the outer side in the axial direction of the lock ring is expanded to raise the protruding portion toward the outer surface of the bead core and to stand outward in the radial direction. Raising step,
In a state where the ply turn-up ring is expanded, the ply turn-up ring is moved laterally inward in the axial direction, so that it is located radially outside the outer peripheral surface of the bead core. A tilting step of tilting the overhang portion toward the outer peripheral surface of the bead core;
And a pressing step of pressing the overhanging protruding portion against the outer peripheral surface of the bead core using a stitch roller.   The stitch roller is composed of a concavo-convex roller in which the roller surface repeats irregularities in the circumferential direction and a smooth roller having a smooth surface as the roller surface, and is pressed by the concavo-convex roller prior to the smooth roller. The method for forming a green tire according to claim 1.   The carcass winding step includes a wrapping step of fixing a portion pressed by the pressing step to an outer peripheral surface of the bead core with a wrapping wire wound outside in the radial direction. A method for forming a green tire as described. A central drum capable of expanding and contracting, in which a cylindrical carcass cylinder is formed by winding a sheet-like carcass ply around the outer peripheral surface so as to be rotatably held by the drum central shaft portion;
From a proximity state in which the outer end portion of the carcass tube is disposed on both sides in the axial direction of the central drum and protrudes outward in the axial direction from the central drum in the vicinity of the central drum, the axial direction from the outer end portion A side drum that can move inward and outward in the axial direction between the outer side and a separated state that is separated by a distance D;
In the first slide case, the side drum is held on the drum central shaft portion so as to be integrally rotatable with the central drum, and can move in and out in the axial direction between the proximity state and the separation state.
A bead lock means having a lock ring capable of expanding and contracting to hold a bead core that is extrapolated to the outer end portion by expanding the diameter;
A winding means that is arranged on the outer side in the axial direction of the bead lock means and winds a protruding portion of the carcass tube that is axially outer than the bead core, around the bead core;
The winding means is configured such that the protruding portion of the bead core is formed by expanding the diameter of the bead core on a second slide case that is disposed on the first slide case so as to be movable inward and outward in the axial direction relative to the first slide case. It has a ply turn-up ring that can be expanded and contracted to rise radially outward toward the outer surface,
In addition, the ply turn-up ring has an outer peripheral surface of the bead core in the rising portion by the relative movement of the second slide case in the axial direction in a state in which the ply turn-up ring is expanded. An apparatus for forming a raw tire, characterized in that a protruding portion on the outer side in the radial direction is tilted toward the outer peripheral surface of the bead core.

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