Method for manufacturing pneumatic tires

Abstract

To provide a method of manufacturing a pneumatic tire that can suppress adhesion of a first case to a bead lock without applying a special process to the bead lock.SOLUTION: A method of manufacturing a pneumatic tire includes assembling a pair of beads 16 on both axial sides of a carcass band 11 to form a first case 10, expanding the diameter of the bead lock 32 in the drum radial direction to fix the first case 10 on the outer circumference of a pair of shaping drums 31, moving the pair of shaping drums 31 closer to each other in the drum axial direction thereby inflating the first case 10 in the drum radial direction to bond a second case 20 containing a tread 23 to form a green tire 100, and vulcanizing and molding the green tire 100 in a tire vulcanizing mold. The removal of the green tire 100 from the pair of shaping drums 31 involves separating the pair of shaping drums 31 from each other in the drum axis direction.SELECTED DRAWING: Figure 5D

Description

[Technical Field]

[0001] The present invention relates to a method for manufacturing a pneumatic tire. [Background technology]

[0002] It is known to manufacture a pneumatic tire by forming a green tire by expanding a first case, which has beads assembled to both sides of a carcass band, radially outward and joining it to the inner periphery of a second case including a tread, and then vulcanizing the green tire.To form the green tire, both sides of the first case are supported by the outer peripheries of a pair of shaping drums, and fluid is supplied to the inside of the first case while the pair of shaping drums are moved toward each other, causing the first case to expand radially outward in the drum direction.

[0003] The shaping drum has a bead lock that can expand and contract in the radial direction of the drum. The bead lock has a lock groove that extends in the circumferential direction and presses against the inner diameter side of the first case where the bead is located to fix it.

[0004] When the first case is fixed by the beadlock, the first case is pressed strongly against the groove bottom surface of the locking groove. Furthermore, when the pair of shaping drums are moved toward each other, the first case is pressed strongly against the groove outer surface that forms the axially outer side of the locking groove. As a result, in the formed green tire, the bead portion may adhere strongly to the groove bottom surface and the groove outer surface of the beadlock locking groove, which may make it difficult to remove the green tire from the locking groove.

[0005] Patent Document 1 discloses that in order to prevent the first case from sticking closely to the bead lock, the outer surface of the area of ​​the bead lock that supports the bead is given a ridge finish or fabric finish, and then a silicone finish is applied on top of that. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Laid-Open No. 2012-35481 Summary of the Invention [Problem to be solved by the invention]

[0007] According to Patent Document 1, in order to prevent the first case from sticking closely to the bead lock, it is necessary to perform a special process on the bead lock.

[0008] An object of the present invention is to provide a method for manufacturing a pneumatic tire that can suppress adhesion of a first case to a bead lock when forming a green tire without performing special processing on the bead lock. [Means for solving the problem]

[0009] The present invention provides A pair of beads are assembled on both axial sides of a carcass band having a cylindrically wound carcass ply to form a first case; Both axial ends of the first case are supported on the outer peripheries of a pair of shaping drums, and each of the pair of shaping drums is provided with a bead lock that forms a part of the outer periphery, is expandable and contractible in the drum radial direction, and has a lock groove that presses against and fixes an area of ​​the first case where the bead is located, The bead lock is expanded in a drum radial direction to fix the first case onto the outer periphery of the pair of shaping drums, The pair of shaping drums are moved toward each other in the drum axial direction, thereby causing the first case to bulge outward in the drum radial direction, and the first case is bonded to a second case including a tread disposed on the radially outer side to form a green tire; removing the green tire from the pair of shaping drums; vulcanizing and molding the green tire in a tire vulcanizing mold; Including, The green tire is removed by separating the pair of shaping drums from each other in the drum axial direction. After that, the bead lock is reduced in diameter. The present invention provides a method for manufacturing a pneumatic tire, the method comprising:

[0010] According to the present invention, after forming a green tire, the pair of shaping drums are separated from each other in the drum axial direction, which makes it easier to break the adhesion of the bead portions in the locking grooves. Specifically, by separating the pair of shaping drums from each other in the drum axial direction, the bead portions of the green tire are tilted inward in the drum axial direction, which makes it easier to break the adhesion of the bead portions to the outer groove surfaces of the locking grooves. This improves the work of removing the green tire from the pair of shaping drums. Furthermore, removing the green tire includes narrowing the beadlock diameter after moving the pair of shaping drums away from each other in the drum axial direction. According to this configuration, the bead portions of the green tire are first released from their adhesion to the groove outer surfaces of the locking grooves, and then released from their adhesion to the groove bottom surfaces, thereby enabling the green tire to be more efficiently removed from the pair of shaping drums. Note that if the beadlock diameter is narrowed before moving the pair of shaping drums in the drum axial direction, it may be difficult to release the beadlock from its adhesion to the groove bottom surfaces if the groove outer surfaces of the locking grooves are firmly in adhesion. In this case, even if the pair of shaping drums are then moved away from each other, it is difficult to release the beadlock from its adhesion to the groove bottom surfaces and groove outer surfaces of the locking grooves.

[0013] The green tire may be removed by moving the pair of shaping drums away from each other in the drum axial direction so that the bead portions of the green tire are inclined inward in the drum axial direction at an inclination angle of 65° or more and 75° or less as a result of the separation.

[0014] According to this configuration, the bead portion of the green tire can be inclined appropriately, which makes it easier to separate the bead portion from the locking groove while suppressing separation of the components constituting the green tire due to the inclination. If the inclination angle of the bead portion is less than 65°, the bead portion will be inclined excessively, which may weaken the pressure bond between the bead and the carcass ply and cause separation. On the other hand, if the inclination angle of the bead portion is more than 75°, the inclination amount of the bead portion is insufficient, making it difficult to separate the bead portion from the locking groove in the axially outer portion of the drum.

[0015] The green tire may be removed by moving the pair of shaping drums at a moving speed of 1000 mm / min or more and 5000 mm / min or less when moving the pair of shaping drums away from each other in the drum axial direction.

[0016] According to this configuration, moving the pair of shaping drums at high speed makes it easy to break the adhesion of the bead portion at the outer portion of the locking groove in the drum axial direction. If the moving speed of the shaping drum is less than 1000 mm / min, it is difficult to break the adhesion of the bead portion at the outer portion of the locking groove in the drum axial direction, but if the moving speed of the shaping drum exceeds 5000 mm / min, the deformation of the green tire cannot keep up, and the adhesion between the bead and the carcass ply becomes weak, which may result in separation.

[0017] Removing the green tire may include moving the pair of shaping drums closer to each other in the drum axial direction after moving the pair of shaping drums away from each other in the drum axial direction and before reducing the diameter of the bead locks.

[0018] According to this configuration, by moving the pair of shaping drums in the drum axial direction multiple times, it becomes even easier to break the tight adhesion of the bead portion to the outer side surface of the lock groove.

[0019] Removing the green tire may include moving the pair of shaping drums away from each other in the drum axial direction, then bringing them closer to each other in the drum axial direction, and then further moving the pair of shaping drums away from each other in the drum axial direction while reducing the diameter of the bead locks in the drum radial direction.

[0020] According to this configuration, by moving the pair of shaping drums multiple times in the drum axial direction and then reducing the diameter of the lock drum, it is possible to more reliably remove the tight adhesion of the bead portion from the outer groove surface of the lock groove and then remove the tight adhesion of the bead portion from the groove bottom surface, making it easier to more reliably remove the tight adhesion of the green tire to the lock groove. [Effects of the Invention]

[0021] According to the present invention, adhesion of the first case to the bead lock can be suppressed without performing special processing on the bead lock when forming a green tire. [Brief explanation of the drawings]

[0022] [Figure 1] 1A to 1C are process diagrams illustrating a method for manufacturing a pneumatic tire according to one embodiment of the present invention. [Figure 2] FIG. 3 is a cross-sectional view schematically showing a first case. [Figure 3] FIG. 4 is a cross-sectional view schematically showing a second case. [Figure 4] FIG. 10 is a diagram showing the first case attached to the shaping drum. [Figure 5A] FIG. [Figure 5B] FIG. [Figure 5C] FIG. 10 is a diagram showing the third shaping step. [Figure 5D] FIG. 10 is a diagram showing the fourth shaping step. [Figure 5E] A diagram showing the fifth shaping step. [Figure 5F] FIG. 10 is a diagram showing the process of removing the green tire from the shaping drum. [Figure 6A] A diagram showing the sixth shaping step. [Figure 6B] A diagram showing the seventh shaping step. DETAILED DESCRIPTION OF THE INVENTION

[0023] A method for manufacturing a pneumatic tire according to one embodiment of the present invention will now be described with reference to the accompanying drawings. Note that the following description is merely exemplary in nature and is not intended to limit the present invention, its applications, or its uses.

[0024] 1 is a process diagram showing a method for manufacturing a pneumatic tire according to one embodiment of the present invention. A first case 10 (see FIG. 2) formed in a first case forming process 1 and a second case 20 (see FIG. 3) formed in a second case forming process 2 are joined together in a green tire molding process 3 to form a green tire 100 (see FIG. 5F). Next, in a tire vulcanization process 4, the green tire 100 is vulcanized and molded in a tire vulcanization mold (not shown) to manufacture a pneumatic tire.

[0025] 2 shows a first case 10 formed by cylindrically winding a plurality of tire components around the outer periphery of a first drum 5 (also called a band drum). The first case 10 has a carcass band 11 and a pair of beads 16 assembled on both sides of the drum in the axial direction.

[0026] The carcass band 11 has, in order from the inner diameter side, an inner liner 12 wrapped around the outer periphery of the first drum 5, a pair of sidewalls 13 wrapped around both sides of the drum in the axial direction, a pair of chafers 14 wrapped around the boundary between the inner liner 12 and the sidewalls 13, and a carcass ply 15 wrapped around the pair of sidewalls 13.

[0027] The bead 16 is assembled to the carcass band 11 in the region where the chafer 14 is located in the drum axial direction. The bead 16 has an annular bead core 17 and a bead filler 18 connected to the outer peripheral surface in the tire radial direction. The bead core 17 is configured by covering an annular bundle formed by winding a bead wire made of steel wire multiple times with rubber. The bead filler 18 is formed in a triangular shape that narrows in the drum axial direction toward the outer radial direction of the drum.

[0028] 3 shows a second case 20 formed by winding a plurality of tire components around the outer periphery of a second drum 6 (also referred to as a belt drum). The second case 20 has a belt 21, a reinforcing belt 22, and a tread 23, which are wound in this order around the outer periphery of the second drum 6. The belt 21 includes a first belt 21a and a second belt 21b laminated on the outer diameter side of the first belt 21a. The first belt 21a is wider in the drum axial direction than the second belt 21b.

[0029] The green tire building process 3 will now be described. Fig. 4 shows a schematic diagram of a shaping device 30. A simplified first case 10 and second case 20 are also shown in Fig. 4. The shaping device 30 is a device that combines the first case 10 and the second case 20 to build a green tire 100. The shaping device 30 has a pair of shaping drums 31 that face each other with a gap in the drum axial direction.

[0030] The pair of shaping drums 31 are driven to rotate about the drum axis by a driving means (not shown) and are configured to be movable toward and away from each other. The periphery of each shaping drum 31 is provided with a beadlock 32 that forms part of the periphery, is arranged on the inside in the drum axial direction, and is capable of expanding and contracting in the drum radial direction, and a turn-up arm 35 that is arranged adjacent to the outside of the beadlock 32 in the drum axial direction.

[0031] The bead lock 32 is an annular body having a lock groove 33 extending circumferentially around the entire outer periphery. The positions of the pair of shaping drums 31 in the drum axial direction are adjusted so that when the first case 10 is placed on the pair of shaping drums 31, the lock groove 33 is positioned in the drum axial direction corresponding to the area of ​​the first case 10 where the bead 16 is located.

[0032] The locking groove 33 is recessed inward in the drum radial direction and has a groove bottom surface 33a, a groove outer side surface 33b extending outward in the drum radial direction from the outer edge of the groove bottom surface 33a in the drum axial direction, and a groove inner side surface 33c extending outward in the drum radial direction from the inner edge of the groove bottom surface 33a in the drum axial direction.

[0033] The groove width W1 of the locking groove 33 is greater than the width W2 in the drum axial direction of the portion including the bead core 17 and the carcass band 11 folded back around the bead core 17. The groove bottom surface 33a may be connected to the groove outer side surface 33b and the groove inner side surface 33c by corner R having a curvature radius of 2 mm to 20 mm. The groove outer side surface 33b and the groove inner side surface 33c are perpendicular to the groove bottom surface 33a. The groove depth of the locking groove 33 is sufficient to accommodate the bead core 17, and is, for example, 5 mm to 10 mm.

[0034] A plurality of turn-up arms 35 are provided at intervals in the circumferential direction along the outer periphery of the shaping drum 31, and each extends in the drum axial direction. A base end 35a of each turn-up arm 35 is pivotally supported by a moving body 36 so as to be swingable in the drum radial direction. A roller 37 is rotatably provided on a tip end 35b of each turn-up arm 35.

[0035] An annular elastic ring 38 is attached to the outer periphery of the base end portions 35a of the multiple turn-up arms 35 arranged in the circumferential direction. The elastic ring 38 biases the multiple turn-up arms 35 radially inward around the base end portions 35a of the drum.

[0036] The moving body 36 is configured to be movable in the drum axial direction along the outer peripheral surface of the shaping drum 31 by a driving means (for example, a conveying means using a cylinder or a ball screw, etc.) not shown.

[0037] 5A to 5F, the green tire building process 3 will be described. As shown in FIG. 5A, in the first shaping process, the bead lock 32 is expanded in diameter, thereby supporting the area of ​​the first case 10 where the bead 16 is located from the inner diameter side by the lock groove 33. As a result, the first case 10 is fixed to the lock groove 33 of the bead lock 32 at the bead 16. At this time, as shown in the enlarged view of FIG. 5A, the first case 10 is in close contact with the groove bottom surface 33a of the lock groove 33 in the drum radial direction.

[0038] 5B, in the second shaping step, a pair of shaping drums 31 are moved toward each other in the drum axial direction while fluid (e.g., compressed air) is supplied to the inside of the first case 10, causing the first case 10 to bulge outward in the tire radial direction between the pair of beads 16, forming the first case main body 10A, which is then bonded to the inner circumferential surface of the second case 20 disposed radially outward. At this time, a tread stitcher (not shown) presses the second case 20 against the first case main body 10A, and the two are pressure-bonded together in the drum radial direction.

[0039] 5B, the first case 10 is pressed inward in the drum axial direction by the groove outer surface 33b of the locking groove 33, so that the first case 10 is in close contact with the groove outer surface 33b of the locking groove 33 in the drum axial direction. That is, the first case 10 is in close contact with the groove bottom surface 33a and groove outer surface 33b of the locking groove 33.

[0040] 5C, in a third shaping step, the movable body 36 is moved inward in the drum axial direction, so that the base ends 35a of the turnup arms 35 move inward in the drum axial direction, and the rollers 37 at the tip ends 35b move outward in the drum radial direction along both side edges of the first case main body 10A. The rollers 37 of the turnup arms 35 fold back the first case side portions 10B of the first case 10 that are positioned outward in the drum axial direction from the bead 16, starting from the bead 16, toward the inside in the drum axial direction and press-fit them against both side edges of the first case main body 10A.

[0041] This forms a green tire 100 in which the first case 10 and the second case 20 are joined together. Although not shown in the drawings, after the green tire 100 is formed, the movable body 36 is moved outward in the drum axial direction, whereby the turn-up arm 35 returns to its initial position where its tip 35b is positioned on the outer periphery of the shaping drum 31. In the green tire 100, the bead 16 and the bead portion 110 formed by the first case 10 folded back around the bead 16 are tightly adhered to each other at the groove bottom surface 33a and the groove outer surface 33b in the lock groove 33.

[0042] 5D , in a fourth shaping step, the pair of shaping drums 31 are moved outward in the drum axial direction so as to separate from each other. Specifically, the pair of shaping drums 31 are moved outward in the drum axial direction so that the separation distance between the groove outer surfaces 33b of the respective locking grooves 33 becomes L1. As a result, the bead portions 110 of the green tire 100 are inclined inward in the drum axial direction toward the outer side in the drum radial direction, and therefore, the tight contact of the groove outer surfaces 33b of the locking grooves 33 with the bead portions 110 in the drum axial direction is peeled off or relaxed.

[0043] Here, the separation distance L1 is calculated by the following formula (1) so that the bead portion 110 of the green tire 100 is inclined at an inclination angle X of 65° or more and 75° or less toward the outer side in the drum radial direction and toward the inner side in the drum width direction. In formula (1), B1 is the belt width of the first belt 21a, and H1 is the bulging height of the first case 10 in the drum radial direction. In formula (1), 20 mm is added to the belt width B1 in consideration of the thickness of the sidewall 13 in order to estimate the width dimension in the drum axial direction at the inner peripheral surface of the second case 20 based on the belt width B1 of the first belt 21a.

[0044]

number

[0045] Preferably, the pair of shaping drums 31 are configured to move apart outward in the drum axial direction at a moving speed of 1000 mm / min to 5000 mm / min, inclusive. At this time, the amount of movement of the pair of shaping drums 31 outward in the drum axial direction is, for example, 8 mm to 20 mm.

[0046] 5E, in a fifth shaping step, the bead lock 32 is reduced in diameter, thereby causing the adhesion of the bead portion 110 to the groove bottom surface 33a of the lock groove 33 in the drum radial direction to be released or relaxed.

[0047] 5F, the green tire 100 is removed from the pair of shaping drums 31. At this time, the bead portions 110 of the green tire 100 are no longer in close contact with the lock grooves 33, so the green tire 100 can be easily removed from the pair of shaping drums 31.

[0048] According to the green tire building process 3 according to the above embodiment, the following effects are achieved.

[0049] (1) After forming the green tire 100, the pair of shaping drums 31 are moved away from each other in the drum axial direction, which makes it easier to break the tight adhesion of the bead portions 110 in the lock grooves 33. Specifically, by moving the pair of shaping drums 31 away from each other in the drum axial direction, the bead portions 110 of the green tire 100 are tilted inward in the drum axial direction, which makes it easier to break the tight adhesion of the bead portions 110 to the groove outer surfaces 33b of the lock grooves 33. This improves the work of removing the green tire 100 from the pair of shaping drums 31.

[0050] (2) The green tire 100 is removed from the pair of shaping drums 31 by moving the pair of shaping drums 31 away from each other in the drum axial direction and then reducing the diameter of the bead locks 32. As a result, the bead portions 110 of the green tire 100 are released from the groove outer side surfaces 33b of the lock grooves 33, and then released from the groove bottom surfaces 33a, thereby enabling the green tire 100 to be more efficiently removed from the pair of shaping drums 31.

[0051] If the bead locks 32 are reduced in diameter before the pair of shaping drums 31 are moved in the drum axial direction, it may be difficult to separate the groove bottom surfaces 33a from the groove outer surfaces 33b of the lock grooves 33 when they are tightly adhered to each other. In this case, even if the pair of shaping drums 31 are then moved away from each other, it is difficult to separate the groove bottom surfaces 33a from the lock grooves 33.

[0052] (3) When the pair of shaping drums 31 are moved away from each other in the drum axial direction, the pair of shaping drums 31 are moved so that the bead portions 110 of the green tire 100 are tilted inward in the drum axial direction at an inclination angle X of 65° or more and 75° or less due to the separation. As a result, the bead portions 110 of the green tire 100 can be tilted appropriately, thereby suppressing separation of the components constituting the green tire 100 due to the inclination.

[0053] If the inclination angle X of the bead portion 110 is less than 65°, the bead portion 110 will be excessively inclined, which will weaken the pressure bond between the bead portion 110 and the carcass ply 15 and may result in separation. On the other hand, if the inclination angle X of the bead portion 110 exceeds 75°, the inclination amount of the bead portion 110 will be insufficient, making it difficult to separate the bead portion 110 from the groove outer surface 33b of the lock groove 33.

[0054] (4) By moving the pair of shaping drums 31 outward in the drum axial direction at a speed of 1000 mm / min or more and 5000 mm / min or less, the bead portion 110 can be easily released from the groove outer surface 33b of the lock groove 33.

[0055] If the moving speed of the shaping drum 31 is less than 1000 mm / min, it is difficult to separate the bead portion 110 from the groove outer surface 33b of the lock groove 33. On the other hand, if the moving speed of the shaping drum 31 exceeds 5000 mm / min, the deformation of the green tire 100 cannot keep up, and the pressure between the bead 16 and the carcass ply 15 weakens, which may cause separation.

[0056] The present invention is not limited to the configurations described in the above embodiments, and various modifications are possible.

[0057] In the above embodiment, after the green tire 100 is formed, the pair of shaping drums 31 are moved outward in the drum axial direction only once, and then the bead locks 32 are reduced in diameter, but this is not limiting.

[0058] For example, following the state shown in Fig. 5D, i.e., after the pair of shaping drums 31 are moved away from each other, the pair of shaping drums 31 may be moved inward in the drum axial direction so as to approach each other as a sixth shaping step, as shown in Fig. 6A. Furthermore, as a seventh shaping step, the pair of shaping drums 31 may be moved outward in the drum axial direction so as to move away from each other, while reducing the diameter of the beadlocks 32 as shown in Fig. 6B.

[0059] By moving the pair of shaping drums 31 in the drum axial direction a plurality of times, the tight adhesion of the bead portion 110 to the groove outer side surface 33b of the lock groove 33 can be more easily removed.

[0060] Furthermore, by reducing the diameter of the bead lock 32 after moving the pair of shaping drums 31 in the drum axial direction multiple times, the bead portion 110 can be more reliably released from its tight contact with the groove outer surface 33b of the lock groove 33, and then the bead portion 110 can be released from its tight contact with the groove bottom surface 33a of the lock groove 33, making it easier to more reliably release the tight contact of the bead portion 110 of the green tire 100 with the lock groove 33.

[0061] Furthermore, by reducing the diameter of the bead locks 32 simultaneously with the second axial outward movement of the pair of shaping drums 31, the cycle time of the green tire building process 3 can be shortened compared to when these steps are performed separately.

[0062] In addition, after forming the green tire 100, the pair of shaping drums 31 may be moved back and forth two or more times in the drum axial direction, such as moving outward, inward, outward, inward, outward in the drum axial direction.

[0063] In the above embodiment, the first case 10 is described as an example in which the carcass ply 15 is not folded back around the bead 16, but the present invention can also be similarly applied to a first case in which the carcass ply 15 is folded back around the bead 16.

[0064] An adhesion prevention structure may be formed to prevent the bead portion 110 of the green tire 100 from adhering to the groove outer surface 33b of the lock groove 33. Various structures can be adopted as the adhesion prevention structure, and for example, a single ridge extending in the drum circumferential direction and projecting inward in the drum axial direction may be formed, or multiple ridges arranged concentrically may be formed. [Explanation of symbols]

[0065] 1. First case forming process 2. Second case forming process 3 Green tire molding process 4. Tire vulcanization process 5. First Drum 6. Second drum 10 Case 1 11 Carcass Band 15 Carcass ply 16 beads 17 Bead core 18 Bead filler 20 Case 2 21a First Belt 23 Tread 30 Shaping Device 31 Shaping Drum 32 beadlock 33 Lock groove 33a Groove bottom surface 33b Groove outer surface 35 Turn-up arm 100 Green Tires 110 Bead section X Tilt angle

Claims

1. A pair of beads are assembled on both axial sides of a carcass band having a cylindrically wound carcass ply to form a first case; Both axial ends of the first case are supported on the outer peripheries of a pair of shaping drums, and each of the pair of shaping drums is provided with a bead lock that forms a part of the outer periphery, is expandable and contractible in the drum radial direction, and has a lock groove that presses against and fixes an area of ​​the first case where the bead is located, The bead lock is expanded in a drum radial direction to fix the first case onto the outer periphery of the pair of shaping drums, the pair of shaping drums are moved toward each other in the drum axial direction, thereby causing the first case to bulge outward in the drum radial direction, and the first case is bonded to a second case including a tread disposed on the radially outer side thereof to form a green tire; removing the green tire from the pair of shaping drums; vulcanizing and molding the green tire in a tire vulcanization mold; Including, The method for manufacturing a pneumatic tire includes removing the green tire by moving the pair of shaping drums away from each other in the drum axial direction and then reducing the diameter of the bead lock.

2. The green tire is removed by moving the pair of shaping drums apart from each other in the drum axial direction so that the bead portions of the green tire are inclined inward in the drum axial direction at an inclination angle of 65° to 75° as a result of the separation. A method for manufacturing the pneumatic tire according to claim 1.

3. In removing the green tire, the pair of shaping drums are moved at a moving speed of 1000 mm / min or more and 5000 mm / min or less when they are separated from each other in the drum axial direction. The method for manufacturing the pneumatic tire according to claim 1 or 2.

4. removing the green tire includes moving the pair of shaping drums closer to each other in the drum axial direction after moving the pair of shaping drums away from each other in the drum axial direction and before reducing the diameter of the bead locks; A method for manufacturing a pneumatic tire according to any one of claims 1 to 3.

5. removing the green tire includes moving the pair of shaping drums away from each other in the drum axial direction, then moving them close to each other in the drum axial direction, and then reducing the diameter of the bead locks in the drum radial direction while further moving the pair of shaping drums away from each other in the drum axial direction; The method for manufacturing the pneumatic tire according to claim 4.

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