JP4568415B2 - Method and apparatus for forming cylindrical green - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention provides an unvulcanized rubber material and a reinforcing cord that constitute an air spring sleeve, which is used, for example, as a suspension member of an automobile, or to be mounted on a shock absorber or a suspension trat to exert a function as an air spring. More specifically, the present invention relates to a forming method and a forming apparatus for a cylindrical green formed by overlapping and forming into a cylindrical shape, and more specifically, to a forming method and a forming apparatus for a cylindrical green having beads having the same diameter at both ends in the cylinder axis direction. Is.
[0002]
[Prior art]
As a method for forming this type of cylindrical green, the following processes and means have generally been employed. That is,
First step: As shown in FIG. 18, each of the arc-shaped segments 21 divided into a plurality (indicated by six in the drawing) in the circumferential direction is divided into the order of (1) to (6) in FIG. After assembling each segment 21 as shown in FIG. 19, a cylindrical molding drum 23 that is configured to be assembled and disassembled by moving in the reverse order in the radial direction and assembled and disassembled. A sheet-like cylindrical member 24, that is, two or one of an inner rubber 24A and a reinforcing cord 24B is wound around the outer periphery of the forming drum 23.
At this time, since the length in the cylinder axial direction of the sheet-like cylindrical member 24 is larger than the axial width of the forming drum 23, both end portions 24a, 24a in the axial direction of the sheet-like cylindrical member 24 are provided on both sides of the forming drum 23. Are attached to the main shaft 22 so as to be removable.
[0003]
Second step: After removing the auxiliary drums 25, 25 on both sides, as shown in FIG. 20, both end portions 24a, 24a of the sheet-like tube member 24 are formed into a cylinder axis by manual operation using hand rolls 26, 26. Fold it down and turn it down.
Third step: As shown in FIG. 21, the beads 27, 27 are pressed against the outer surfaces of the turn-down portions 24a, 24a at both ends of the sheet-like cylindrical member 24, and temporarily fixed and held.
Fourth step: As shown in FIG. 22, both ends are turned down so as to wrap the beads 27, 27 by pressing the dedicated turn-up rollers 28, 28 inside the both ends turn-down portions 24a, 24a of the sheet-like cylinder member 24. The portions 24a and 24a are turned outwardly and turned up.
[0004]
Fifth step: As shown in FIG. 23, after covering rubber 29 around the outer periphery of the sheet-like cylinder member 24 including both end turn-up portions 24a, 24a of the sheet-like cylinder member 24, each of the molding drums 23 is formed. The forming drum 23 is disassembled by moving the segment 21 in the radial direction, and the formed cylindrical green G is removed.
[0005]
[Problems to be solved by the invention]
In the conventional cylindrical green molding method comprising the above-described steps, if the turn-down in the second step and the turn-up in the fourth step are performed at once, for example, by an automatic machine, wrinkles or the like are generated in the sheet-like cylindrical member 24. Therefore, in order to improve the yield of the product (cylindrical green), it is inevitably necessary to perform it manually by an expert using the dedicated rollers 26 and 28. Further, when removing the mold after molding, it is necessary to disassemble the divided segments 21 constituting the forming drum 23, and the disassembly requires a lot of time and labor. As a result, the molding efficiency is very poor and takes time, which tends to increase costs. In addition, there is a problem in that quality is not stable and product performance varies due to manual turn-down and turn-up.
[0006]
The present invention has been made in view of the above circumstances, and is a cylinder that can obtain a high-quality cylindrical green that does not generate wrinkles while automating the majority of the molding process to significantly improve the molding efficiency. It aims at providing the shaping | molding method and shaping | molding apparatus of green.
[0007]
[Means for Solving the Problems]
In order to achieve the above object, a method for forming a cylindrical green according to the present invention as set forth in claim 1 is a method for forming a cylindrical green having beads having the same diameter at both ends in the cylindrical axis direction, and having an enlarged or reduced diameter. A step of winding a sheet-like cylindrical member around the outer periphery of the molding drum in a state in which the diameter of the segment of the cylindrical molding drum having a changeable segment is expanded, and the molding drum on both sides in the cylindrical axial direction of the molding drum A pair of cylinders that are arranged so as to be able to move in the distance and have an inclined portion that gradually increases in diameter as it approaches the forming drum, and that can be reduced and deformed against the inclination of the inclined portion against elasticity. The cylindrical elastic fingers are moved closer to the forming drum side, so that both end portions of the cylindrical cylindrical member of the sheet-like cylindrical member correspond to the inclination gradient of the inclined portion of the cylindrical elastic finger and are reserved on the cylindrical axis side. And a pair of bead set rings that can hold the bead and move close to the molding drum side, respectively, on both sides of the molding drum in the cylinder axis direction so as to be movable relative to the molding drum. By causing the inclined slope of the cylindrical elastic finger to be reduced and deformed, both end portions in the cylindrical axis direction of the sheet-like cylindrical member are turned down to the final shape and simultaneously held by the pair of bead set rings. A step of setting the bead at both end turn-down portions of the sheet-like cylinder member, and a pair of bladders arranged at both ends in the cylinder axis direction of the molding drum and configured to be able to expand and contract by gas injection / discharge By expanding and deforming, the both ends turn-down portions of the sheet-like cylindrical member are pulled outward from the diameter, and gradually from the inner diameter side of the bead. Crimping to the bead by preliminarily turning it up and pressing the pair of expanded beads by moving the pair of bead set rings close to the forming drum again and pushing them inward in the cylinder axis direction A step of turning up both end portions of the sheet-shaped cylindrical member that has been preliminarily turned up to a final shape, a step of winding a cover rubber around the outer periphery of the sheet-shaped cylindrical member including the both end turn-up portions, and the above molding And a step of demolding the cylindrical green formed by reducing the diameter of the drum segment.
[0008]
According to a third aspect of the present invention, there is provided a cylindrical green molding apparatus according to the present invention, which is a cylindrical green molding apparatus having beads having the same diameter at both ends in the cylindrical axis direction, and has segments that can be expanded and contracted. And a forming drum that can be formed by winding a sheet-like cylindrical member around the outer periphery of the segment in a diameter-enlarged state, and disposed on both sides in the cylindrical axis direction of the forming drum so as to be movable relative to the forming drum. A pair of cylindrical elastic fingers for turndown having an inclined portion that gradually increases in diameter as it approaches the forming drum, and formed to be capable of reducing deformation against the inclination of the inclined portion against elasticity; and The cylindrical elastic fingers are arranged on both sides of the molding drum in the cylinder axial direction so as to be movable relative to the molding drum, can hold the beads, and move closer to the molding drum. A pair of bead set rings that can be deformed to reduce the slope of the slope of the slope, and both ends of the molding drum in the cylinder axis direction can be expanded and contracted by gas injection / discharge. Along with expansion by gas injection, a pair of turn-up bladders that gradually press the inner end of the bead while pulling both ends of the sheet-like cylindrical member outward, and expansion / contraction deformation by gas injection / discharge And a segment operation bladder for changing the expansion / contraction diameter of the segment of the molding drum by the expansion / contraction deformation.
[0009]
According to the method of the present invention including the above steps and the device of the present invention including the above-described configurations, a pair of cylindrical elastic fingers and a pair of bead set rings are formed after the sheet-shaped cylindrical member is wound around the outer periphery of the forming drum. It is possible to automate the turn-down and bead setting at both ends of the sheet-like cylindrical member by sequentially moving closer to the forming drum side, and the pair of bladders are expanded after the turn-down, and a pair of bead sets It is possible to automate the turn-up of both ends of the sheet-like cylindrical member by moving only the ring again toward the forming drum.
Forming by automating the turndown, bid setting and turnup, which have been done by manual work in this way, by moving the cylindrical elastic fingers and bead set rings in the cylinder axis direction and expanding the bladder by gas injection The time can be greatly shortened, and the cylindrical green molded on the outer periphery of the drum can be removed simply by reducing the diameter of the molding drum segment without disassembling the molding drum as in the past. Therefore, the demolding time can be greatly shortened.
[0010]
In addition, turn-down and turn-up are both automated, and turn-down and turn-up are performed in two stages, ie, preforming and final forming, without forming defects such as wrinkles. Moreover, it is possible to stably form a high-quality cylindrical green without causing variations among individual products.
[0011]
In particular, in the cylindrical green molding apparatus according to the present invention, by using a common bag as a segment operation bladder and a pair of turn-up bladders as a means for changing the diameter of a segment, the same specification is achieved. It is only necessary to prepare one type of bag, and the cost of the entire apparatus can be reduced.
[0012]
Further, in the cylindrical green molding apparatus according to the present invention, the leaf spring finger pieces divided into a plurality in the circumferential direction are arranged closely in the circumferential direction as the cylindrical elastic fingers for turndown. It is possible to apply to the formation of multiple cylindrical greens with different diameters by increasing or decreasing the number of leaf spring finger pieces arranged in the circumferential direction. Can increase the sex.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a longitudinal front view of the entire cylindrical green molding apparatus according to the present invention, FIG. 2 is a longitudinal front view of the upper half part of the molding apparatus, and this molding apparatus undergoes a molding process to be described later. Finally, as shown in FIG. 17, it is used when a cylindrical green G having beads 5 and 5 having the same diameter at both ends in the cylinder axis direction is formed.
[0014]
The cylindrical green molding apparatus is roughly divided and arranged concentrically on the outer periphery of the main shaft 11 concentrically connected and fixed to the end of the rotating shaft 10, and the sheet-like cylindrical member 3 can be wound around the outer periphery thereof. A cylindrical forming drum 2, a pair of turn-down cylindrical elastic fingers 4, 4 and a pair of bead set rings 6, 6 disposed on both sides of the forming drum 2 in the cylinder axis direction; A pair of turnup bladders 7 and 7 disposed at both ends in the axial direction and a segment operation bladder 9 for changing the diameter of the plurality of segments 1 forming the forming drum 2 are provided.
[0015]
As shown in FIG. 3, the molding drum 2 is composed of segments 1... Divided into a plurality of parts in the circumferential direction. These segments 1 are expanded in diameter by moving inward and outward through slide supports 1a provided between the main shaft 11 and the expansion / contraction deformation of the bladder 9 (the right half of FIG. 3). ) And a reduced diameter state (left half state in FIG. 3), and a rubber band 12 is provided on the outer periphery of the segments 1. Is wound.
[0016]
As shown in FIGS. 4 and 5, the pair of turn-down cylindrical elastic fingers 4 includes a leaf spring finger piece 4 </ b> A having a substantially trapezoidal shape in a side view divided into a plurality of portions in the circumferential direction. Closely arranged. On the free end side of these finger pieces 4A, there are formed inclined portions 4a that gradually increase in diameter as they approach the forming drum 2, and the base end portions 4b of the finger pieces 4A are not shown. It is fixed to the end of a cylinder shaft 13 that is driven and moved in the cylinder axis direction via a cylinder device or the like, and this cylindrical elastic finger 4 is moved close to the molding drum 2 side via the cylinder device and the cylinder shaft 13. Then, the inclined portions 4a of the finger pieces 4A are brought into contact with the end portion 3a of the sheet-like cylindrical member 3 in the cylinder axis direction, as indicated by the phantom lines in the upper half of the axis in FIG. The end portion 3a of the cylindrical member 3 is configured to be capable of being preliminarily turned down to the cylindrical axis side in correspondence with the inclination gradient of the inclined portions 4a.
[0017]
The pair of bead set rings 6 are configured such that a ring-shaped main body 6A having a slightly larger diameter than the cylindrical elastic finger 4 is configured to be movable in the cylinder axis direction via a cylinder device (not shown). A holding portion 6B of a bead 5 is provided at the end of the main body 6A on the molding drum 2 side, and the bead set ring 6 is moved close to the molding drum 2 side via a cylinder device to hold the holding portion 6B. Are brought into contact with the inclined portions 4a of the finger pieces 4A of the cylindrical elastic finger 4, so that the inclined gradients of the inclined portions 4a are reduced and deformed against elasticity, so that the sheet-like cylindrical member 3 is deformed. The end portion 3a is turned down to the final shape, and the held bead 5 can be set on the end turndown portion 3a of the sheet-like cylindrical member 3.
[0018]
The pair of turn-up bladders 7 and segment operation bladders 9 are formed inside the rotary shaft 10 and the main shaft 11 and are pressurized from a gas, specifically from a compressor (not shown) through a through-hole 14 connected to each other. It consists of a common airbag that can be expanded and contracted by injecting and discharging air. Among them, as shown in the lower half of the axis of FIG. 1, the turnup bladder 7 pulls the end turndown portion 3 a of the sheet-like cylindrical member 3 to the outside of the diameter as it expands by injecting high-pressure air. It is comprised in the state which can be crimped | bonded gradually from the side. Further, the segment operation bladder 9 is expanded and contracted due to the injection / discharge of high-pressure air, so that the segments 1... Of the forming drum 2 are reduced in diameter in the upper half of the axis in FIG. It is comprised so that it may change to a diameter state.
[0019]
Reference numerals 15 and 15 in FIGS. 1 and 2 denote auxiliary drums attached to both ends of the forming drum 2, which can be replaced according to the length of the sheet-like cylindrical member 3 in the cylinder axis direction.
[0020]
Next, a method of forming a cylindrical green G as shown in FIG. 17 having beads 5 and 5 having the same diameter at both ends in the axial direction using the forming apparatus configured as described above is illustrated in the order of steps (FIG. 6 to 16). 6 to 16, only the upper half portion of the main axis 11 is shown, but the lower half portion is symmetrical with the upper half portion with the axis line as a boundary (center).
[0021]
First step (initial state): As shown in FIG. 6, high-pressure air is injected into the segment operation bladder 9 to expand the diameter of the segments 1 of the molding drum 2 and to hold the pair of bead set rings 6 and 6. The beads 5 are set in the parts 6B and 6b, respectively.
2nd process (winding shaping | molding): As shown in FIG. 7, the sheet-like cylinder member 3 is wound around the outer periphery of the segment 1 ... of the shaping | molding drum 2. As shown in FIG. Here, as shown in FIG. 17, the sheet-like cylinder member 3 is composed of two or one of an inner rubber 3A and a reinforcing cord 3B.
Third step (preliminary turndown): As shown in FIG. 8, the pair of cylindrical elastic fingers 4, 4 are respectively moved close to the forming drum 2 side, and the inclined portions 4 a, 4 a. Are brought into contact with both end portions 3a, 3a of the sheet-like cylindrical member 3, so that both end portions 3a, 3a correspond to the inclination gradients of the inclined portions 4a, 4a ... of the finger pieces 4A, 4A ... Preliminarily turn down.
4th process-5th process (final turndown): As shown in FIGS. 9-10, a pair of bead set rings 6 and 6 are moved to the forming drum 2 side, respectively, and the end of bead holding | maintenance part 6B, 6B Are brought into contact with the inclined portions 4a, 4a ... of the finger pieces 4A, 4A ... of the cylindrical elastic fingers 4, 4 to reduce the inclination gradient of the inclined portions 4a, 4a ... Then, both end portions 3a, 3a of the sheet-like cylinder member 3 are turned down to the final shape.
Sixth step (bead set): As shown in FIG. 11, at the same time as the turndown to the final shape is completed, the beads 5 and 5 held by the bead holding portions 6B and 6B of the pair of bead set rings 6 and 6 are used. Is set on the outside of the turn-down portions 3a, 3a at both ends, and then the pair of bead set rings 6, 6 and the cylindrical elastic fingers 4, 4 are moved away from the forming drum 2 to achieve a predetermined turn-down. Exit.
[0022]
Seventh step (preliminary turn-up): As shown in FIG. 12, high-pressure air is injected into a pair of turn-up bladders 7 and 7 to expand and deform the bladders 7 and 7 so that both ends of the sheet-like cylindrical member 3 While pulling down the turn-down portions 3a, 3a to the outside of the diameter, the beads 5 and 5 are gradually pressed from the inner diameter side to be preliminarily turned up.
Steps 8 to 9 (final turn-up): As shown in FIG. 13, the pair of bead set rings 6 and 6 are again moved closer to the forming drum 2 side to expand and deform the bladders 7 and 7 into the cylinder axis. As shown in FIG. 14, after both end portions 3 a and 3 a of the sheet-like cylindrical member 3 that has been preliminarily turned up and pressed with the beads 5 and 5 are turned up to the final shape by pushing inward in the direction. In addition, the pair of bead set rings 6 and 6 are moved away from the forming drum 2, and high pressure air is discharged from the bladders 7 and 7 to cause shrinkage deformation, thereby completing a predetermined turnup.
[0023]
Tenth step (cover rubber winding): As shown in FIG. 15, the cover rubber 8 made of the same material as the inner rubber 3A is wound around the outer periphery of the sheet-like cylindrical member 3 including the turn-up portions 3a, 3a at both ends. To do.
Eleventh step (demolding): As shown in FIG. 16, by discharging high-pressure air from the segment operation bladder 9 and contracting and deforming this bladder 9, the segments 1 of the molding drum 2 are reduced in diameter. A gap is formed between the beads 5, 5 and the segments 1, and the cylindrical green G formed on the outer periphery of the forming drum 2 is extracted in the cylinder axis direction and removed.
[0024]
As described in the first step to the eleventh step above, a pair of turndown and turnup with respect to both end portions 3a and 3a in the cylindrical axis direction of the sheet-like cylindrical member 3 which has been conventionally performed manually using a roll is a pair. The cylindrical elastic fingers 4 and 4 and the pair of bead set rings 6 and 6 and the pair of bladders 7 and 7 are not only automated by operations, but also without disassembling the segment 1 of the forming drum 2. It is possible to remove the cylindrical green G formed on the outer periphery of the drum 2 simply by reducing the diameter of the segment 1 of the forming drum 2 through the bladder 9, and the molding time including demolding is considerably long. Shortening can be achieved.
[0025]
In addition to automating turn-down and turn-up, the turn-down and turn-up are performed in two stages: pre-forming and final forming, so that high quality can be achieved without generating defects such as wrinkles. The cylindrical green G can be molded stably.
[0026]
【The invention's effect】
As described above, according to the present invention, it is possible to automate most of the molding processes such as turn-down and turn-up that have been conventionally performed manually, and to eliminate the work of disassembling the molding drum that requires a great amount of work and time. By enabling easy and quick demolding, it is possible to achieve a significant improvement in molding efficiency by greatly shortening the molding time. By performing the two steps, there is an effect that it is possible to always stably and stably form a high-quality cylindrical green having no generation of wrinkles while being automated with high molding efficiency.
[Brief description of the drawings]
FIG. 1 is a longitudinal front view of a whole cylindrical green forming apparatus according to the present invention.
FIG. 2 is a longitudinal sectional view of an upper half portion from the axis of the molding apparatus.
FIG. 3 is an enlarged side view showing a configuration of a molding drum in the molding apparatus.
FIG. 4 is an enlarged side view of a cylindrical elastic finger in the molding apparatus.
FIG. 5 is an enlarged longitudinal sectional front view of the same cylindrical elastic finger.
FIG. 6 is a longitudinal front view of the upper half portion of the axis showing the first step of the cylindrical green molding step.
FIG. 7 is a longitudinal front view of the upper half portion of the axis showing the second step of the molding step.
FIG. 8 is a longitudinal front view of the upper half portion of the axis showing the third step of the molding step.
FIG. 9 is a longitudinal front view of the upper half portion of the axis showing the fourth step of the molding step.
FIG. 10 is a longitudinal front view of the upper half portion of the axis showing the fifth step of the molding step.
FIG. 11 is a longitudinal front view of the upper half portion of the axis showing the sixth step of the molding step.
FIG. 12 is a longitudinal front view of the upper half portion of the axis showing the seventh step of the molding step.
FIG. 13 is a longitudinal front view of the upper half portion of the axis showing the eighth step of the molding step.
FIG. 14 is a longitudinal front view of the upper half portion of the axis showing the ninth step of the molding step.
FIG. 15 is a longitudinal front view of the upper half portion of the axis showing the tenth step of the molding step.
FIG. 16 is a longitudinal front view of the upper half portion of the axis showing the eleventh step of the molding step.
FIG. 17 is a partially omitted vertical cross-sectional view of a molded cylindrical green.
FIG. 18 is an enlarged side view showing a schematic configuration of a molding drum used in conventional cylindrical green molding.
FIG. 19 is a longitudinal front view of the upper half of the axis showing a first step of a conventional cylindrical green molding step.
FIG. 20 is a longitudinal front view of the upper half portion of the axis showing the second step of the conventional molding step.
FIG. 21 is a longitudinal front view of the upper half portion of the axis showing the third step of the conventional molding step.
FIG. 22 is a longitudinal front view of the upper half portion of the axis showing the fourth step of the conventional molding step.
FIG. 23 is a longitudinal front view of the upper half portion of the axis showing the fifth step of the conventional molding step.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Segment 2 Forming drum 3 Sheet-shaped cylinder member 3a End part 4 of sheet-shaped cylinder member 4 Tube elastic finger 4A Leaf spring finger piece 4a Inclined part 5 Bead 6 Bead set ring 7 Turn-up bladder 8 Cover rubber 9 For segment operation Bladder G Tube green

Claims (5)

A method for forming a cylindrical green having beads of the same diameter at both ends in the cylinder axis direction,
A step of winding a sheet-like cylindrical member around the outer periphery of the molding drum in a state where the diameter of the segment of the cylindrical molding drum having a segment capable of changing the expansion and contraction diameter is increased;
The molding drum is disposed on both sides in the cylinder axis direction so as to be movable relative to the molding drum, and has an inclined portion that gradually increases in diameter as it approaches the molding drum, and the inclination gradient of the inclined portion is By moving the pair of cylindrical elastic fingers formed so as to be able to reduce and deform against the elasticity close to the forming drum side, both end portions in the cylindrical axis direction of the sheet-shaped cylindrical member are moved to the inclined portions of the cylindrical elastic fingers. A step of preliminarily turning down to the cylinder axis side corresponding to the inclination gradient;
A pair of bead set rings which are arranged on both sides in the cylinder axial direction of the molding drum so as to be movable relative to the molding drum and which can hold beads are respectively moved closer to the molding drum side to move the cylindrical elastic fingers. By reducing and deforming the inclination gradient of the inclined portion of the sheet-shaped cylindrical member, both end portions in the cylindrical axis direction of the sheet-shaped cylindrical member are turned down to the final shape, and at the same time, the beads held by the pair of bead set rings are A process of setting both ends of the turndown part;
By expanding and deforming a pair of bladders arranged at both ends in the cylinder axis direction of the molding drum and configured to be expandable / shrinkable by gas injection / discharge, the turndown portions at both ends of the sheet-like cylinder member are reduced in diameter. A step of preliminarily turning up by gradually pressing from the inner diameter side of the bead while pulling outward,
The pair of bead set rings are moved closer to the forming drum side again and the expanded pair of bladders are pushed inward in the cylinder axis direction, so that the sheet-like cylinder member is pressure-bonded to the bead and preliminarily turned up. A step of turning up both end portions to a final shape;
A process of wrapping and molding a cover rubber around the outer periphery of the sheet-like cylindrical member including its both-end turn-up portions;
Removing the cylindrical green molded by reducing the diameter of the molding drum segment;
A method of forming a cylindrical green, comprising: The cylindrical green molding method according to claim 1, wherein a bladder configured to be able to expand and contract by gas injection / discharge is used as means for changing the expansion / contraction diameter of the segment in the molding drum. A cylindrical green molding device having beads of the same diameter at both ends in the cylinder axis direction,
A molding drum having a segment that can be expanded and contracted and capable of winding a sheet-like cylindrical member around the outer periphery of the segment in an expanded state;
The molding drum is disposed on both sides in the cylindrical axis direction so as to be movable relative to the molding drum, and has an inclined portion that gradually increases in diameter as it approaches the molding drum, and has an inclination gradient of the inclined portion. A pair of turn-down cylindrical elastic fingers formed to be able to shrink and deform against elasticity;
The cylindrical elastic fingers are arranged on both sides in the cylinder axial direction of the molding drum so as to be movable relative to the molding drum, can hold a bead, and the inclined portion of the cylindrical elastic finger is moved closer to the molding drum. A pair of bead set rings capable of reducing and deforming the slope of
It is arranged at both ends in the cylinder axis direction of the molding drum, and can be expanded / contracted by gas injection / discharge, while pulling the both ends of the sheet-shaped cylinder member to the outside of the diameter as expansion by gas injection. A pair of turn-up bladders that are gradually crimped from the inner diameter side of the bead;
A segment operation bladder that can be expanded / contracted by gas injection / discharge, and the expansion / contraction deformation of the segment of the molding drum can be changed.
A cylindrical green molding apparatus characterized by comprising: 4. The cylindrical green molding apparatus according to claim 3, wherein the pair of turn-up bladders and segment operation bladders are configured using a common bag. The cylindrical green molding device according to claim 3, wherein the turn-down cylindrical elastic fingers are configured by closely arranging leaf spring finger pieces divided into a plurality in the circumferential direction in the circumferential direction. .

Images