JPH0818089B2 - Flexible tube and manufacturing method thereof - Google Patents

Description

Detailed Description of the Invention

[0001]

The present invention relates to a flexible tube,
More specifically, it relates to improvements in flexible tubes used for various types of piping.

[0002]

2. Description of the Related Art Generally, this kind of flexible tube has been widely used for various pipes because it can absorb bending and twisting during piping work easily and can perform piping work easily. Conventionally, as a manufacturing method thereof, for example, there is a means such as a sleeve forming method and a pipe expanding method, and by this, a large number of annular bulging portions are continuously provided on the flexible tube body.

A joint is usually connected to the end portion of the tube body, and a packing is attached to the peripheral surface of the end portion of the tube body so as to interpose a seal packing between the joint and the tube body. Is provided with a collar against which

In this case, as shown in FIG. 3 (a), in the cueing method in which the flexible tube body 1a has the straight tube portion 1b at the end thereof and the bulging portion 2 is continuously provided, the same figure ( (2) Using the straight pipe portion 1b, a collar 3a which is an abutting surface on the end side is formed.
Is provided.

On the other hand, in the case of the pipe expanding method, as shown in FIG. 4 (a), only the bulging portion 2 having no straight pipe portion is continuously connected to the tube body 1a, so that the flange 3a is provided at the end portion. After the bulging portion 2 on the side is stretched to form a straight pipe portion, a collar 3a is formed at the end of the straight pipe portion as shown in FIG.

[0006]

However, since the straight tube portion 1b is formed at both ends of the above-mentioned conventional tube main body, such a portion does not have flexibility,
As a result, there is a fatal problem that the vibration absorption that the flexible tube should have is significantly reduced.

Therefore, the present invention has been made to solve the above-mentioned conventional problems, and an object thereof is to provide a flexible tube having excellent vibration damping property and easy to manufacture, and a manufacturing method thereof.

[0008]

Means for Solving the Problems That is, the means adopted by the present invention for solving the above-mentioned problems is that a flexible tube main body 1 is provided with a large number of annular bulging portions 2 in series, and The bulging portion 5 located in the portion is formed to have a larger diameter than the other bulging portions 2, and the inner walls of the bulging portion 5 are in close contact with each other.

Further, in the method for manufacturing a flexible tube according to the present invention, after a large number of annular bulging portions 2 are continuously arranged on the peripheral surface of the flexible tube body 1, at least two bulging portions located on the end side are located. It is characterized in that the bulging portion 5 having a larger diameter than the bulging portion 2 is formed by pressing the valley portion 4 between the two from the inside.

[0010]

Therefore, in the flexible tube having the above structure, the tube body 1 is formed by connecting the bulging portion 2 and the large-diameter bulging portion 5 in series. Flexibility is provided throughout.

When a joint is connected to the tube body 1, the large-diameter bulging portion 5 serves as a contact surface of the packing, and a seal between them is achieved.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the flexible tube according to the present invention will be described below with reference to the drawings.

In FIG. 1, reference numeral 1 denotes a flexible tube body made of thin-walled stainless steel, and a large number of annular bulging portions 2 are continuously formed on the peripheral surface of the tube body 1 by a so-called pipe expanding method. Has been done.

Collars 3 are provided at both ends of the tube body 1 and have a diameter larger than that of the bulging portion 2.
As shown in FIG. 2 (a), the collar 3 presses the valley portion 4 between the two bulging portions 2a and 2b located on the end side of the bulging portion 2 from the inside in the arrow A direction. After forming the arcuate bulging portion 5,
In order to bring the inner wall into close contact, it is formed by pressing it in the axial direction (direction of arrow B) as shown in FIG.

Reference numeral 6 is a press ring fitted and attached to the end portion of the tube body 1, and has a flange portion 6a provided at one end thereof for abutting against the back surface of the flange 3 of the tube body 1.

Reference numeral 7 denotes a blade externally fitted to the tube body 1, and its end is fixed to the peripheral surface of the press ring 6 by a fixing ring 8.

Reference numeral 9 denotes a tubular cap nut 10 fitted to the end of the tube body 1, and a nipple screwed to the cap nut 10.
11 shows a joint composed of 11 and an annular packing 12 interposed between the front end surface of the nipple 11 and the front surface of the collar 3 of the tube body 1 to achieve a seal therebetween.

This embodiment is constructed as described above, and such a flexible tube is used as a hydraulic pipe in a press machine or the like in which high speed fluid flows.

Since there is no straight pipe portion in the tube body 1 and the annular bulging portion 2 is formed on the entire peripheral surface, the tube body 1 is flexible due to the presence of the straight pipe portion. The property is not impaired, and good flexibility is provided over the entire structure, so that an excellent vibration damping effect can be obtained.

Further, the collars 3 provided at both ends of the tube body 1
Is formed of two bulging portions 2a and 2b, the contact area with the packing 12 is sufficiently secured, and as a result, the seal between the tube body 1 and the joint 9 can be reliably performed. is there.

Further, since the collar 3 can be formed extremely easily as described above, there is an advantage that the collar 3 can be manufactured inexpensively without complicating a series of manufacturing operations.

In the above embodiment, the flange 3 having a large diameter is formed from the two bulged portions 2 on the end side, but the bulge 3 may be formed from more bulged portions 2. Of course it is possible.

A joint 9 connected to the tube body 1
The specific configuration of (1) is not limited and can be changed according to the device or the like to be connected, but the joint 9 is not necessarily provided in the tube body 1.

In addition, the means for forming the bulging portion 2 of the tube body 1 is not limited to the tube expanding method of the above embodiment, and any means can be used as long as it can connect a large number of annular bulging portions 2.

[0025]

As described above, according to the present invention, a large number of bulging portions having a diameter larger than that of the bulging portion are continuously formed on an annular bulging portion continuously provided on the flexible tube body. Unlike the conventional tube body, since there is no straight pipe portion at all, the presence of this straight pipe portion does not impair flexibility.

Therefore, as a result of providing the entire tube with excellent flexibility, it is possible to obtain a particular effect that the vibration damping property is significantly improved as compared with the conventional one.

Moreover, when the joint is connected to the tube body, the bulging portion with which the sealing packing abuts is formed to have a large diameter as described above, and the inner walls thereof are in close contact with each other. The contact area is secured, and there is also an effect that a good sealing property is obtained.

Further, the large-diameter bulging portion can be manufactured very easily, and since the whole structure is simple, there is a practical effect that it can be manufactured at low cost.

[Brief description of drawings]

FIG. 1 is a half sectional view showing an embodiment of a flexible tube according to the present invention.

2A and 2B are enlarged cross-sectional views of a main part showing a step of forming a bulging portion.

3A and 3B are half-cut sectional views showing a conventional example.

4A and 4B are half-cut sectional views showing a conventional example.

[Explanation of symbols]

 1 ... Flexible tube main body 2 ... Bulging part 3 ... Collar 4 ... Valley part 5 ... Bulging part 6 ... Press ring 6a ... Collar part 7 ... Blade 8 ... Fixing ring 9 ... Joint 10 ... Cap nut 11 ... Nipple 12 ... Packing

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI technical display area F16L 33/00 33/28

Claims (7)

[Claims] 1. A flexible tube body (1) having an annular shape.
In a flexible tube with a large number of bulging parts (2)
The bulge (5) at the end of the bulge (2)
Is also formed with a large diameter, and the inner walls of the bulging portion (5) are in close contact with each other.
Flexible tube characterized by being made . 2. The end of the flexible tube body (1)
The flexi according to claim 1, wherein a joint (9) is connected to the portion.
Bull tube . 3. The flexible tube as the joint (9).
The tubular cap nut (10) attached to the body (1) and the bag nut
A nipple (11) screwed to the port (10), and
Swelling of the apple (11) and the flexible tube body (1)
A packing (12) is interposed between the front faces of the parts (5).
Item 2. A flexible tube according to item 2 . 4. The end of the flexible tube body (1)
The press ring (6) is fitted and attached to the
The flexible tube body (1) is fitted onto the ring (6).
The end of the squeezed blade (7) is secured by the retaining ring (8).
The flexi according to any one of claims 1 to 3,
Bull tube . 5. The flexible ring is attached to one end of the press ring (6).
Collar (6a) that abuts the bulging part (5) of the sibble tube body (1)
5. The flexible chew according to claim 4, wherein
Boo . 6. A flexible tube main body (1) is provided with a peripheral surface thereof.
Located on the end side after connecting a number of annular bulges (2)
Push the valley (4) between at least two bulges (2) from the inside.
A bulging part having a diameter larger than that of the bulging part (2) by pressing.
Flexible tube characterized by forming (5)
Manufacturing method . 7. Crush the large-diameter bulge (5) in the axial direction.
Close the inner walls to each other to form a collar (3).
The method for manufacturing a flexible tube according to claim 6 .