JPH06238745A - Rubber tube bending apparatus and method - Google Patents

Abstract

PURPOSE:To enhance the working efficiency of assembling work, etc., by bending a rubber tube to easily and accurately attach the same to a ring member. CONSTITUTION:After a rubber tube 6 is inserted in a holder 15 through an outer ring 7, a piston rod 13 is extended to displace respective clamping pawl parts 16 to the outside of the diameter direction of the tube 6 and the rubber tube 6 is pressed and fixed to the inner peripheral surface of the holder 15 and one end part 6A of the rubber tube 6 is expanded to the outside in the diameter direction thereof by respective expanding pawl parts 21. By extending the piston rod 24B of a folding-back cylinder 24 in this state, the rubber tube 6 is inserted in the expanding pawl parts 21 along with the outer ring 7 and one end part 6A is folded back on the upper end side of the outer ring 7 to be attached to the outer ring 7.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rubber tube bending apparatus and a rubber tube bending method suitable for bending a rubber tube for an air suspension and attaching it to an outer ring.

[0002]

2. Description of the Related Art Generally, an air suspension used as a suspension device for a vehicle such as an automobile is provided with a shock absorber main body having a piston rod expandable and contractable, and a shock absorber main body provided on the piston rod protruding end side. A tubular outer shell with a lid that covers the outside of the shock absorber body, and a rubber tube that is provided between the inner peripheral side of the outer shell and the outer peripheral side of the shock absorber body and defines an air chamber inside,
One end of the rubber tube is fixed by caulking to the inner peripheral side of the outer shell via an outer ring, and the other end is fixed to the outer peripheral side of the shock absorber body via a base ring.

Then, the rubber tube is inserted into the outer ring by an operator, and one end of the rubber tube is folded back to the outside of the outer ring so that the rubber tube is attached to the outer ring to form a tube-ring assembly. This tube-ring assembly will be attached to the outer shell and shock absorber body in the next step.

[0004]

By the way, since the bending of the rubber tube according to the above-mentioned prior art is manually performed by the operator, the folded dimension of the rubber tube and the like are stabilized with high accuracy as designed. In addition, it is difficult to carry out, and it takes a lot of time to assemble, resulting in low assembly efficiency. In particular, the rubber tube for the air suspension is provided with a reinforcing wire mesh, so it is difficult to bend it, and it is difficult to obtain the prescribed accuracy. There is a problem that it will increase.

Further, since the rubber tube has the characteristics of flexibility and high frictional force, it is difficult to automate the bending process of the rubber tube, the process is complicated, and the manufacturing efficiency of the entire air suspension is reduced. There's a problem.

The present invention has been made in view of the above-described problems of the prior art. A rubber tube can be bent and easily attached to a ring member, and the work efficiency of assembling work can be greatly improved. An object is to provide a tube bending device and a rubber tube bending method.

[0007]

In order to solve the above-mentioned problems, the structure adopted by the rubber tube bending apparatus according to the present invention is such that the rubber tube is inserted into the inner peripheral side and the rubber tube is inserted into the upper end side. A cylindrical holder on which a ring member can be placed while being fitted to the outer peripheral side of the holder, and a clamp provided on the inner peripheral side of the holder for pressing and fixing the rubber tube on the inner peripheral surface of the holder Means, and a plurality of diameter-increasing claw portions that are inserted into the upper opening of the rubber tube fixed by the clamping means and that radially expand to the outside of the ring member to expand the upper end side of the rubber tube, By inserting the ring member into the inner peripheral side of each of the diameter-increasing claws while the upper end side of the rubber tube is expanded by each of the diameter-increasing claws, the rubber tube is inserted into the ring portion. Comprising a folding means folded back at the upper end of the.

The rubber tube bending method according to the present invention employs a rubber tube inserting step of inserting the rubber tube into the inner peripheral side of the ring member, a clamping step of fixing the rubber tube, and a clamping step of the rubber tube. The process includes a diameter expanding step of expanding the upper end side of the rubber tube fixed in the step, and a folding back step of folding the rubber tube at the upper end side of the ring member with the upper end side of the rubber tube expanded in the diameter expanding step.

[0009]

[Operation] With the configuration of the rubber tube bending device,
When the rubber tube is inserted into the holder and the ring member is fitted to the outer circumference of the rubber tube, the rubber tube is fixed by the clamp means, and the plurality of diameter-increasing claw portions are radially extended to the outside of the ring member. The upper end side of the rubber tube is expanded by moving the rubber tube. And
When the folding member further inserts the ring member into the inner peripheral side of each diameter-enlarging claw portion with the upper end side of the rubber tube expanded, the rubber tube is thereby folded and attached at the upper end side of the ring member.

According to the construction of the rubber tube bending method, the rubber tube is inserted into the inner peripheral side of the ring member in the rubber tube inserting step, the rubber tube is fixed in the clamping step, and then the rubber tube is expanded in the diameter expanding step. When the upper end side of the tube is widened and the rubber tube is folded back at the upper end side of the ring member in the folding step in this state, the rubber tube is bent and attached to the ring member.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. 1 to 9 by taking a case where the rubber tube of an air suspension is used as an example.

First, FIGS. 1 to 7 relate to a first embodiment of the present invention. In the drawings, 1 is a shock absorber body whose lower end side is attached to an axle side through an attachment eye (not shown), and 2 is a shock absorber body. The piston rods are respectively shown to project axially upward from the upper end side of the shock absorber body 1, and the piston rods 2 are
The lower end of the bumper body 1 enters the shock absorber body 1 and is attached to a piston (not shown), and the upper end of the bumper rubber 3 and the like protrudes to the outside of an outer shell 4 to be described later to attach an attachment eye (not shown). It is attached to the vehicle body side through.

Reference numeral 4 denotes an outer shell which is located on the outer peripheral side of the shock absorber body 1 and is attached to the protruding end side of the piston rod 2. The outer shell 4 is formed in a cylindrical shape having a large diameter and having a lid.
The opening extends downward so as to cover the shock absorber body 1. A rubber tube 6 to be described later is caulked and fixed to the inner peripheral side of the lower end of the outer shell 4, and is displaced axially in accordance with the expansion and contraction of the piston rod 2 together with the rubber tube 6.

Reference numeral 5 denotes a tubular member which is located below the outer shell 4 and is provided on the outer peripheral side of the shock absorber main body 1. The lower end side of the tubular member 5 is an axially intermediate portion of the shock absorber main body 1. The upper end side extends upward so as to surround the shock absorber body 1.

Reference numeral 6 denotes a rubber tube which defines an airtight air chamber A between the outer shell 4 and the tubular member 5, and the rubber tube 6 is formed of an elastic material such as rubber into a tubular shape. Here, the rubber tube 6 is attached to the outer circumference of an outer ring 7 which is a ring member having one end 6A located on the outer circumference side and formed in a cylindrical shape with rigidity from a metal material or the like. The outer shell 4 is fixed by caulking the lower end side from the outer peripheral side. The other end 6B located on the inner peripheral side is fixed to the upper end outer peripheral side of the tubular member 5 via the base ring 8. The rubber tube 6 has a cross section U at its middle portion.
When the outer shell 4 is axially displaced together with the piston rod 2 by being folded back in a letter shape, the air chamber A is contracted and expanded following this displacement.

Reference numeral 9 denotes a vehicle height adjusting electromagnetic valve mounted on the outer peripheral side of the outer shell 4, and the electromagnetic valve 9 is connected to a compressor (neither is shown) or the like via an air pipe. The electromagnetic valve 9 supplies compressed air from a compressor or the like into the air chamber A to displace the piston rod 2 and the outer shell 4 upward, while discharging the compressed air in the air chamber A to an air pipe. Is used to displace the piston rod 2 and the like downward.

Next, one end 6A of the rubber tube 6
A device for bending the rubber tube 6 for bending so as to be positioned on the outer circumference of the outer ring 7 will be described with reference to FIGS. 2 to 7.

Reference numeral 10 designates clamp claw portions 16, 16 to be described later.
1 shows a cylinder for clamping, which includes a cylinder body 11 including a lower cylinder portion 11A and an upper cylinder portion 11B, and the cylinder body 1.
1, a piston 12 slidably provided, a lower end side thereof is fixed to the piston 12, and an upper end side thereof is a cylinder body 11
And a guide portion 13A that is formed at the uppermost portion of the piston rod 13 and is formed in the shape of a small diameter rod, and the guide portion 13A.
Upper taper portion 13B which is located on the lower side of the upper taper portion 13B and which is formed by successively reducing the diameter upward, and a lower side which is spaced apart from the lower side of the upper taper portion 13B and which is formed by successively reducing the diameter upward. A taper portion 13C is provided. Further, a support plate 14 that projects radially outward is formed on the outer peripheral side of the upper cylinder portion 11B of the cylinder body 11, and mounting members 19, 19 described later are mounted on the support plate 14. Then, the clamp cylinder 10 expands and contracts the piston rod 13 by supplying and discharging pressure oil from the outside, and the clamp claw portions 16 are radially extended via the taper portions 13B and 13C of the piston rod 13. Each is to be displaced.

Reference numeral 15 denotes a cylindrical holder which is located on the outer peripheral side of the clamping cylinder 10 and is provided on the upper cylindrical portion 11B of the cylinder body 11, and the inner peripheral surface of the holder 15 is gradually expanded upward. It is formed in a tapered shape. And
An outer ring 7 is placed on the upper end side of the holder 15 via a ring supporting member 20 described later, and the rubber tube 6 is inserted via the outer ring 7.

Reference numerals 16, 16, ... Denote four clamping claw portions (only two are shown) as clamping means provided on the inner peripheral side of the holder 15 so as to be spaced apart from each other in the circumferential direction. The portion 16 has two spring grooves 16A, which are axially separated from each other.
16A are formed by cutting out in the circumferential direction, and each spring groove 16
C-shaped springs 17, 17 for urging the clamping claw portions 16 toward the inner peripheral side are provided in A, respectively. Also,
The inner peripheral side of each clamp claw portion 16 is a piston rod 13
Is formed in a tapered shape corresponding to each of the tapered portions 13B and 13C.

When the piston rod 13 is contracted, the clamp claw portions 16 are urged inward by the springs 17 and come into contact with the top plate portion 18A of the clamp support member 18, which will be described later. When the piston rod 13 extends upward, the taper portions 13B, 1 of the piston rod 13
It is urged radially outward by 3C, is displaced radially outward against the spring force of each spring 17, and presses and fixes the rubber tube 6 on the inner peripheral surface of the holder 15.

Reference numeral 18 denotes a clamp support member located above the cylinder body 11 and provided on the inner peripheral side of each clamp claw portion 16. The clamp support member 18 has the guide portion 13A of the piston rod 13 An annular top plate portion 18A to be inserted and four leg portions 18B, 18B extending from the top plate portion 18A into the gaps between the clamp claw portions 16 respectively.
... (only two are shown) and the upper cylinder portion 1 of the cylinder body 11
1B and a pedestal portion 18C to which the lower ends of the respective leg portions 18B are connected.

Reference numerals 19 and 19 denote two mounting members provided on the support plate 14 so as to be spaced apart from each other in the circumferential direction. Reference numeral 20 denotes a cylindrical member which is located on the outer peripheral side of the holder 15 and is mounted on each mounting member 19. Each of the ring support members is shown, and the outer ring 7 is placed on the upper end side of the ring support member 20, that is, on the upper end side of the holder 15.

Clamping cylinders 10, 21 ...
The four diameter-increasing claw portions 2 (only two of which are shown in the figure) are shown facing each other and spaced apart in the circumferential direction.
1 is movably provided in a radial direction along a long groove (not shown) provided in the guide portion 22, and is moved via a cam follower 23 by a cam mechanism (not shown). Then, each of the diameter-increasing claws 21 has a cam follower 23
By moving in the radial direction to the outside of the outer ring 7, one end 6A of the rubber tube 6 is widened.

Reference numeral 24 denotes a folding cylinder as a folding means provided on the lower side of the clamping cylinder 10,
The folding cylinder 24 is composed of a cylinder body 24A accommodating a piston (not shown) and a piston rod 24B projecting axially upward from the cylinder body 24A and having a lower end side fixed to the piston. The protruding end side of the rod 24B is the clamping cylinder 10.
It is attached to the bottom of the lower tube portion 11A. Then, the folding cylinder 24 is used for each of the diameter-increasing claw portions 21 as described later.
When the upper end side of the rubber tube 6 is expanded by, the rubber tube 6 and the outer ring 7 are moved axially upward together with the clamping cylinder 10, and the outer ring 7 is inserted into the inner peripheral side of each diameter-expanding claw portion 21. By doing
The rubber tube 6 is folded back.

The rubber tube bending apparatus according to this embodiment has the above-mentioned structure, and its operation will be described below with reference to FIGS. 3 to 7.

First, FIG. 3 shows a rubber tube insertion step of inserting the rubber tube 6 into the outer ring 7. In the rubber tube insertion step, the piston rod 24B of the folding cylinder 24 is contracted so as to clamp the cylinder 1 for clamping.
After arranging 0, etc. as a whole on the lower side, the piston rod 13 of the clamping cylinder 10 is contracted to displace the clamping claw portions 16 inward in the radial direction. A gap is formed with the holder 15.
Next, the outer ring 7 is attached to the upper end side of the ring supporting member 20.
Then, the rubber tube 6 is inserted into the holder 15 via the outer ring 7.

Then, in the clamping step shown in FIG. 4, the piston rod 13 of the clamping cylinder 10 is extended and the tapered portions 13B and 13C of the piston rod 13 are expanded.
The clamp claw portions 16 are displaced radially outward by. As a result, the rubber tube 6 inserted into the holder 15 in the rubber tube inserting step is pressed against the inner peripheral surface of the holder 15 by the clamp claw portions 16 and is firmly fixed.

Next, in the step of inserting the diameter-increasing claw portion shown in FIG. 5, the piston rod 24B of the folding cylinder 24 is extended by a predetermined amount, and the clamping cylinder 10, the rubber tube 6, the outer ring 7, etc. are raised. By
The diameter-expanding claw portions 21 are inserted into the rubber tube 6 fixed in the clamping step.

Further, in the diameter expanding step shown in FIG. 6, each diameter expanding claw portion 21 inserted into the rubber tube 6 in the diameter expanding claw insertion step is outer ringed by a cam mechanism via a cam follower 23. 7 is moved to the outside in the radial direction, and one end 6A side of the rubber tube 6 is pushed outward in the radial direction.

In the folding step shown in FIG. 7, the piston rod 24B of the folding cylinder 24 is further extended, and the rubber tube 6 whose one end 6A side has been expanded by the diameter expanding step together with the outer ring 7 and the like. It inserts in the inner peripheral side of each diameter expansion claw portion 21. As a result, one end 6A of the rubber tube 6 is folded back at the upper end side of the outer ring 7 and bent and attached to the outer ring 7 to form a tube-ring assembly.

Finally, in a take-out step (not shown), the piston rod 24B of the folding cylinder 24 is contracted to separate the rubber tube 6 and the like from the diameter-increasing claw portions 21, and the clamping claw portions 16 are used. The fixing is released, the rubber tube 6 and the outer ring 7 are taken out from the holder 15 and conveyed to the next step.

Thus, according to the present embodiment, the rubber tube 6 inserted into the holder 15 via the outer ring 7 is fixed by the clamp claw portions 16 and the diameter expanding claw portions 21 are used. By pushing one end 6A side of 6 outwardly in the radial direction and extending the piston rod 24B of the folding cylinder 24 in this state,
Rubber tube 6 together with outer ring 7
The rubber tube 6 can be inserted into the outer ring 7, and one end 6A of the rubber tube 6 can be folded back at the upper end side of the outer ring 7 and attached to the outer ring 7.

As a result, the rubber tube 6 for the air suspension having high elasticity can be automatically bent and accurately attached to the outer ring 7, and the bending accuracy and the work efficiency of the assembly work can be greatly improved. The cost can be reduced.

Next, FIGS. 8 and 9 show a second embodiment of the present invention. The feature of this embodiment is that a ring support member is provided so as to be vertically movable so that a clearance is provided between the ring and the outer ring. It is possible to bend a rubber tube that does not exist. In this embodiment, the same components as those in the first embodiment shown in FIGS. 1 to 7 described above are designated by the same reference numerals, and the description thereof will be omitted.

In the figure, reference numeral 31 denotes a rubber tube for an air suspension used in this embodiment, and the rubber tube 31 has one end 31A, which is substantially the same as the rubber tube 6 described in the first embodiment. The outer shell 4 is caulked and fixed to the outer shell 4 via the outer ring 7, and the other end 31B is attached to the outer peripheral side of the tubular member 5 via the base ring 8. However, the rubber tube 31 according to the present embodiment has a larger inclination than the rubber tube 6 described in the first embodiment, that is, one end portion 31A opens larger than the other end portion 31B.

Reference numeral 32 denotes a clamping cylinder according to this embodiment. The clamping cylinder 32 is similar to the clamping cylinder 10 described in the first embodiment, and the lower cylinder portion 3 is provided.
Cylinder body 33 including 3A and upper cylinder portion 33B
And a piston 34 slidably provided in the cylinder body 33, and a piston rod 35 having a lower end fixed to the piston 34 and an upper end protruding from the cylinder body 33.
The piston rod 35 is provided with a guide portion 35A, an upper taper portion 35B, and a lower taper portion 35C. However, the clamp cylinder 32 according to the present embodiment is provided with the support plate 36 located on the outer peripheral side of the upper cylindrical portion 33B, and the fixing cylinder 40 described later is attached to the outer peripheral side of the support plate 36. The difference from the first embodiment is that the portion 36A is formed.

Reference numerals 37, 37 denote two ring vertical movement cylinders provided on the support plate 36 so as to be spaced apart from each other in the circumferential direction. The cylinder main body 37A of each ring vertical movement cylinder 37 is attached to the lower surface side of the support plate 36. Piston rod 37
B projects upward through the support plate 36, and the mounting bolt 38
It is attached to the tubular ring support member 39 via. When inserting the rubber tube 31, the ring vertical movement cylinder 37 contracts the piston rod 37B to move the outer ring 7 downward by a predetermined dimension, whereby the other end 31B of the rubber tube 31 is moved. It is intended to ensure that the lower end of the holder 15 is penetrated.

Reference numerals 40 and 40 denote cylinders 3 for vertically moving each ring.
7 shows two fixing cylinders attached to the attachment portion 36A of the support plate 36 corresponding to No. 7, and each fixing cylinder 40
The cylinder body 40A is attached to the outside of the attachment portion 36A, and the piston rod 40B extends radially inward through the attachment portion 36A. In addition, each fixing cylinder 40
A stopper 41 having a substantially U-shaped or C-shaped cross section is attached to the tip end side of the piston rod 40B.

As shown in FIG. 9, each fixing cylinder 40 has a piston rod 40 when the piston rod 37B of each ring vertical movement cylinder 37 extends.
B is extended to bring the stopper 41 into contact with the piston rod 37B of the ring vertical movement cylinder 37, and the stopper 41 is interposed between the ring support member 39 and the support plate 36 to lower the ring support member 39. Support from the side.

Thus, in this embodiment having such a structure, it is possible to obtain substantially the same operation and effect as those of the first embodiment. However, in particular, in this embodiment, each ring vertical movement cylinder 37 is provided on the support plate 36, and the ring support member 3 is provided by each ring vertical movement cylinder 37.
Since 9 is moved up and down, one end portion 31A has a larger opening diameter than the other end portion 31B, and there is no clearance between the rubber tube 31 and the outer ring 7.
However, as shown in FIG. 8, the outer ring 7 can be surely inserted into the holder 15 by moving the outer ring 7 downward in the rubber tube inserting step. After inserting the rubber tube 31 into the holder 15,
In the clamping step, the rubber tube 31 can be fixed by each of the clamping claw portions 16, and then, as shown in FIG.
As shown in, in the ring position adjusting step, the rubber tube 31 can be set easily and reliably by moving the outer ring 7 upward to a predetermined position while fixing the rubber tube 31.

That is, when such a tight rubber tube 31 is applied to the rubber tube bending device described in the first embodiment, before the other end 31B of the rubber tube 31 comes into contact with the cylinder body 11. Moreover, since the intermediate portion of the rubber tube 31 comes into contact with the outer ring 7 and stops, the rubber tube 31 cannot be inserted reliably, and the bending accuracy is significantly reduced. However, in this embodiment, since the outer ring 7 is provided to be vertically movable by each ring vertical movement cylinder 37, the tapered rubber tube 31 can be automatically and accurately bent.

Further, in the present embodiment, the fixing cylinder 40 is provided corresponding to each ring vertical movement cylinder 37, and the stopper 41 is provided at the tip end side of the piston rod 40B of each fixing cylinder 40. Each stopper 41
Thus, the ring support member 39 can be reliably supported. As a result, even when the outer diameter of the outer ring 7 is pressed downward by the rubber tube 31 when the diameter of the rubber tube 31 is expanded, it is possible to reliably prevent the piston rod 37B of each ring vertical movement cylinder 37 from being contracted by this force. However, bending accuracy and reliability can be greatly improved.

In each of the above-described embodiments, four clamp claw portions 16 and four diameter expansion claw portions 21 are provided in the circumferential direction so as to be spaced apart from each other. It is also possible to provide one piece or five or more pieces.

Further, in each of the above embodiments, each mounting member 1
Although the description has been made on the assumption that each of the nine cylinders, the two ring vertical movement cylinders 37, and the like is provided, two cylinders and the like may be provided.

Further, in each of the above-mentioned embodiments, the folding cylinder 24 is provided below the clamping cylinders 10 and 32, and the outer cylinder 7 and the rubber tubes 6, 31 and the like are expanded by the folding cylinder 24. Although described as being inserted into the portion 21, the present invention is not limited to this,
By providing a cylinder on the side of each diameter-increasing claw portion 21 and moving each diameter-increasing claw portion 21 downward by the cylinder,
The outer ring 7 and the like may be relatively inserted into the inner peripheral side of each of the diameter-expanding claw portions 21.

Furthermore, in each of the above-mentioned embodiments, one end 6A of the rubber tube 6 is expanded and at the same time the piston rod 24B of the folding cylinder 24 is expanded.
The one end 6A may be folded back so that the diameter expanding step and the folding step are performed at the same time.

When the inner diameter of the outer ring 7 is larger than the outer diameter of the one end 6A of the rubber tube 6,
The outer ring 7 may be fitted to the outer peripheral side of the rubber tube 6 after the rubber tube 6 is inserted into the holder 15. Further, the rubber tube 6 may be inserted into the holder 15 and fixed by the clamp claw portions 16, and then the outer ring 7 may be fitted to the outer circumference of the rubber tube 6.

[0049]

As described above in detail, according to the rubber tube bending apparatus of the present invention, the rubber tube inserted into the holder and fitted with the ring member is fixed by the clamp means, and the upper end of the rubber tube is fixed. The rubber tube is folded back at the upper end side of the ring member by inserting the ring member into the inner peripheral side of each diameter-increasing claw portion with the side expanded by each diameter-increasing claw portion. It can be bent and attached to a member. As a result, the rubber tube can be automatically bent and accurately attached to the ring member, the bending accuracy and the work efficiency of the assembling work can be improved, and the cost can be reduced.

According to the rubber tube bending method of the present invention, the rubber tube is inserted into the inner peripheral side of the ring member in the rubber tube inserting step, and the rubber tube is fixed in the clamping step, and then the diameter expanding step is performed. The upper end side of the rubber tube is spread with, and the rubber tube is folded back at the upper end side of the ring member in the folding step in this state, so that the rubber tube can be bent and attached to the ring member accurately and automatically. it can.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view showing an air suspension using a rubber tube according to a first embodiment of the present invention.

FIG. 2 is a vertical sectional view showing a rubber tube bending device according to a first embodiment used for bending the rubber tube in FIG.

FIG. 3 is a vertical sectional view similar to FIG. 2, showing a rubber tube inserting step.

FIG. 4 is a vertical sectional view showing a clamping step.

FIG. 5 is a vertical cross-sectional view showing a step of inserting the diameter-increasing claw portion.

FIG. 6 is a vertical sectional view showing a diameter expansion step.

FIG. 7 is a vertical sectional view showing a folding step.

FIG. 8 is a longitudinal sectional view showing a rubber tube bending device according to a second embodiment of the present invention before being clamped.

FIG. 9 is a vertical cross-sectional view showing a state after the rubber tube is clamped.

[Explanation of symbols]

 6, 31 Rubber tube 7 Outer ring (ring member) 15 Holder 16 Claw for clamping (clamping means) 21 Claw for expanding diameter 24 Cylinder for folding (folding means)

Claims (2)

[Claims] 1. A cylindrical holder in which a rubber tube is inserted on the inner peripheral side and a ring member can be mounted on the upper end side while being fitted on the outer peripheral side of the rubber tube, and an inner portion of the holder. Clamping means provided on the circumferential side for pressing and fixing the rubber tube on the inner peripheral surface of the holder, and inserted into the upper opening of the rubber tube fixed by the clamping means, and extending radially to the outside of the ring member. A plurality of diameter-increasing claws that expand the upper end side of the rubber tube by moving the rubber tube, and the ring member with the diameter-increasing claws in a state where the upper end side of the rubber tube is expanded by the respective diameter-increasing claws A rubber tube bending device comprising a folding means for folding the rubber tube at the upper end side of the ring member by further inserting it into the inner peripheral side of the portion. 2. A rubber tube inserting step of inserting a rubber tube into an inner peripheral side of a ring member, a clamping step of fixing the rubber tube, and a diameter expanding step of expanding the upper end side of the rubber tube fixed in the clamping step. And a folding step in which the rubber tube is folded back at the upper end side of the ring member in a state where the upper end side of the rubber tube is widened in the diameter expanding step.