JPH1026266A - Manufacture of flexible pipe and flexible pipe - Google Patents

Abstract

PROBLEM TO BE SOLVED: To facilitate the manufacture of a flexible pipe having a synthetic resin pipe provided with a corrugated pipe part in its cross section by inserting a cylindrical thin line braided blade in the synthetic resin pipe provided with the corrugated pipe part in its cross section externally, inserting a thermal shrinking cylindrical body into these externally, and shrinking the thermal shrinking cylindrical body by heating it. SOLUTION: When a flexible pipe is manufactured, a synthetic resin pipe 1 consisting of a corrugated pipe part in its cross section and a straight pipe part is prepared, and a cylindrical thin line braided blade 3 is mounted on the synthetic resin pipe 1. Next, a thermal shrinking cylindrical body is mounted on the synthetic resin pipe 1 on which the thin line braided blade 3 is mounted, and the thermal shrinking cylindrical body is shrunk to reduce its diameter by heating the thermal shrinking cylindrical body. At this time, the thin line braided blade 3 is pressed toward the center due to heat shrinkage of the thermal shrinking cylindrical body and is pressed against an outer surface of the corrugated pipe part of the synthetic resin pipe 1. Consequently, the thin line braided blade 3 is attached firmly on the outer surface of the synthetic resin pipe 1 by a thermal shrinking covered layer 2 formed due to heat shrinkage of the thermal shrinking cylindrical body.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a flexible tube and a flexible tube, and more particularly, to a flexible tube provided with a synthetic resin tube having a corrugated tube section (bellows-like tube section) and a thin wire braided blade. The present invention relates to a method for manufacturing a flexible tube and a flexible tube.

[0002]

2. Description of the Related Art Conventionally, as a kind of flexible tube, there has been proposed a flexible tube in which a corrugated tube in section is used as an inner tube, and the outer side of the inner tube is covered with a thin braided braid constructed by knitting a thin line for reinforcement. Has been used. This flexible tube has a cross-sectional waveform that makes it easy to bend, and also prevents the inner tube from expanding due to hydraulic pressure with a thin braided braid.

A flexible pipe of this kind is mainly used as a high-pressure fluid transport pipe such as an industrial hydraulic pipe, and a flexible pipe used in such an application has a high internal pressure. In order to withstand, the corrugated tube of the inner tube is made of a metal tube having a relatively high wall pressure, and the braided braid is also made by densely braiding a metal wire having a large tensile strength.

[0004] In this type of flexible pipe, both ends of the thin wire braided blade are firmly attached to both ends of the metal pipe, which is the inner pipe, by welding or mechanical attachment means without slack in the thin wire. The thin braided blade receives an extension force due to the internal pressure of the inner tube at the connecting portions at both ends, and the thin braided blade carries this extension force to prevent the inner tube from extending.

By the way, a flexible pipe comprising an inner pipe having a corrugated cross section as described above and a reinforcing blade is used not only as the above-mentioned hydraulic pipe, but also as other pipes such as a water pipe, a hot water pipe and a sprinkler pipe. It can be used for applications.

[0006] The flexible tube used for such an application is as follows.
Since the working pressure is not so high, a corrugated tube made of synthetic resin can be used for the inner tube. Flexible pipes using synthetic resin inner pipes are easier to bend than metal pipes, especially for water pipes, hot water pipes and sprinklers for general homes and buildings such as buildings. When used in a piping system in which a large number of bent portions must be formed, such as piping, construction is facilitated.

Further, since the synthetic resin is hardly corroded, such a flexible pipe is not corroded even in a place where unclean water or the like stays in the pipe for a long time, especially in a sprinkler pipe. Anomalies such as clogging and water leakage hardly occur.

[0008] Even in such a flexible pipe having a synthetic resin inner pipe, a thin braided braid for reinforcement is brought into close contact with the outer surface of the inner pipe, and the thin wire is covered with no looseness. Must be provided.

This is because when the flexible pipe is used as a hot water pipe, the temperature of the inner pipe becomes high and the synthetic resin inner pipe is softened and easily expanded, and the flexible pipe is used for a sprinkler. This is because, when used as a pipe, a high pressure may be instantaneously applied when the sprinkler is operated or the like, and it is necessary to prevent the pipe from expanding in these cases.

[0010] The thin wire braid used for such a flexible tube does not correspond to a very large force, and therefore, compared with the above-mentioned metal thin wire braid for a high-pressure flexible tube, the braided blade is used. The fine lines are thin and the stitch structure is coarse.

[0011]

However, it is difficult to manufacture a flexible tube using a synthetic resin tube as the inner tube as described above. This is because the thin wires of the thin braided braid are thin and the stitches are coarse, so that the rigidity of the blade itself is low and the blade is easily deformed, so that the attachment of the blade to the inner tube becomes complicated.

In other words, arranging the easily deformable fine-wire braid on the outer surface of the inner tube while keeping the fine wires in a loose state must be performed with care and is time-consuming. Furthermore, when the both ends of the fine wire braid are fixed to both ends of the inner tube, the fine wire of the fine wire braid is thin and the stitch is coarse, so that only the fine wire is sparsely present at the end of the blade. It is troublesome to securely fix the end of the thin wire blade to the end of the inner tube.

Accordingly, the present invention provides a method for manufacturing a flexible tube having a synthetic resin tube provided with a corrugated tube section, and a method for manufacturing the flexible tube. The purpose is to provide sex tubes.

[0014]

In order to solve the above-mentioned problems, a method of manufacturing a flexible tube according to the present invention comprises the steps of: forming a tubular thin wire braided blade 3 on a synthetic resin tube 1 having a corrugated tube section 6; The heat-shrinkable cylinder 5 is extrapolated to these, the heat-shrinkable cylinder 5 is heat-shrinked, and the heat-shrinkable cylinder 5 is fastened to the synthetic resin tube 1 to form the heat-shrinkable coating layer 2. This is a method for manufacturing a flexible tube in which the outer surface of the synthetic resin tube 1 is tightly coated.

Further, in the method for manufacturing a flexible tube according to the present invention, the synthetic resin tube 1 is provided with a straight tube portion 4 at an end portion thereof, and the end portion of the thin wire braided blade is mechanically fixed by a mechanical fixing means 7. To fix it to the straight pipe portion 4.

Further, in order to solve the above-mentioned problem, a flexible tube according to the present invention comprises a synthetic resin tube 1 having a corrugated section 6.
The heat-shrinkable coating layer 2 that has been heat-shrinked and adhered to the synthetic resin tube 1 is in close contact with the outer surface of the synthetic resin tube 1, and is sandwiched between the synthetic resin tube 1 and the heat-shrinkable coating layer 2. It is a flexible tube provided with a thin braided braid 3 arranged.

In the present invention, the synthetic resin pipe 1 is provided with a straight pipe part 4 at an end thereof and a mechanical fixing means 7 for fixing the end of the thin wire braided blade 3 to the straight pipe part 4. it can.

According to the present invention, in manufacturing a flexible tube, the thin braided braid 3 is attached to the synthetic resin tube in close contact with the synthetic resin tube. It is only necessary to extrapolate the braided blades 3, extrapolate the heat-shrinkable cylinder 5 to these, and heat-shrink the heat-shrinkable cylinder 5.

In this manner, the thin wire braided blade 3
The heat-shrinkable tubular body 5 is pressed toward the center by the heat-shrinkable tubular body in accordance with the heat shrinkage, the diameter of the thin wire is reduced while the slackness is extended, and the thin wire is pressed against the outer surface of the synthetic resin pipe 1 as the inner pipe. Can be As a result, the thin-wire braid 3 is constantly pressed inward by the heat-shrinkable coating layer 2 formed by heat-shrinking the heat-shrinkable cylinder, and the fine-wire braid 3 is mechanically attached to the outer surface of the synthetic resin pipe 1. It will be firmly attached. The heat-shrinkable coating layer 2 and the fine-wire braided blade are firmly fixed. Therefore, the synthetic resin pipe 1, the thin braided braid 3, and the heat-shrinkable coating layer 2 are combined with each other, and integrally take the extension force acting on the synthetic resin pipe 1.

Since the manufactured flexible pipe uses the synthetic resin pipe 1 having the corrugated pipe section 6, the flexible pipe can be easily bent and the piping system can be easily constructed. In addition, the thin wire braided blade 3 is attached to the outer surface of the synthetic resin pipe 1 together with the heat shrinkable coating layer 2 by mechanically firmly pressing the same with the heat shrinkable coating layer 2 in the flexible pipe. Therefore, even if the synthetic resin pipe 1 receives an elongation force due to the internal pressure, the synthetic resin pipe 1, the thin wire braided blade 3, and the heat shrinkable coating layer 2 are integrally deformed. For this reason, the extension force is mainly absorbed by the slight extension deformation of the thin wire braid, and large extension in the length direction of the entire flexible tube is prevented.

In the present invention, if necessary, a straight pipe part 4 is provided at the end of the synthetic resin pipe 1, and the end of the thin wire braided blade 3 is fixed to the straight pipe part 4 by mechanical fixing means 7. Therefore, in this case, the thin wire braid blade 3 is more securely attached to the synthetic resin tube 1.

[0022]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a flexible tube according to the present invention will be described below. In this example, first, as shown in FIG. 2, a synthetic resin pipe 1 including a corrugated pipe section 6 and straight pipe sections 4 integrally provided at both ends thereof is prepared. The material of the synthetic resin tube 1 is polyethylene, cross-linked polyethylene,
It is a flexible synthetic resin such as fluororesin,
The material, wall thickness, and cross-sectional shape are appropriately determined as necessary depending on the conditions to be used. The synthetic resin tube 1 is made by a known method.

Although the cross-section corrugated tube portion 6 of the synthetic resin tube main body extends in the length direction by a predetermined amount, only a part thereof is shown in FIG. 2 for convenience of illustration. The same straight pipe section as the illustrated straight pipe section 4 is integrally provided at the opposite end.

Further, as shown in FIG. 3, a tubular thin wire braid blade 3 formed by braiding a thin wire is entirely attached to the synthetic resin pipe 1. At this time, the fine wire braid blade 3
It is not always necessary to adhere to the surface of the synthetic resin pipe 1 in close contact. As shown in FIG. 3, the diameter of the fine-wire braid is formed larger than the diameter of the synthetic resin pipe, and If there is a gap between the synthetic resin pipe 1 and the resin pipe, the thin braided braid can be easily attached to the synthetic resin pipe 1.

The thin braided braid 3 may be applied by covering the synthetic resin pipe 1 with a tubular thin braided braid 3 of a predetermined length prepared in advance, or the thin braided braid 3 around the synthetic resin pipe 1. May be created by knitting.

The thin braided braid 3 is formed by braiding a thin metal wire such as steel. Further, as the thin wire braided blade 3, a thin wire using an organic compound fiber such as aramid fiber or nylon, or a thin wire using a fiber of an inorganic compound such as carbon fiber or glass fiber can be used as necessary. The thickness, material, and density of the stitches are determined according to the required strength.

Next, as shown in FIG. 4, the heat-shrinkable cylindrical body 5 is attached to the synthetic resin pipe 1 to which the thin wire braid blade 3 is attached. This heat-shrinkable cylinder is heat-shrinked later to form the heat-shrinkable coating layer 2.

The heat-shrinkable cylinder 5 is made of ethylene propylene rubber, chloroprene rubber, nitrile butadiene rubber,
A cylindrical body made of synthetic resin such as hard vinyl chloride or cross-linked polyethylene, whose diameter shrinks to about こ と when heated to a predetermined temperature, using a known heat-shrinkable tube. it can.

Then, as shown in FIG. 5, the heat-shrinkable cylinder 5 is heated from the end. Thereby, the heat-shrinkable cylinder 5 shrinks, and its diameter is reduced.

The thin-wire braided blade 3 is entirely pressed toward the center along the heat-shrinkable cylindrical body 5 in accordance with the heat shrinkage of the heat-shrinkable cylindrical body 5 to reduce the diameter of the thin wire while extending the slack of the thin wire. ,
The synthetic resin tube 1 is pressed against the outer surface of the corrugated tube 6. Thus, the thin wire braid blade 3 is constantly pressed inward by the heat shrinkable coating layer 2 formed by heat shrinking the heat-shrinkable cylindrical body 5, and the thin wire braid blade 3 is placed on the outer surface of the synthetic resin tube 1. It will be mechanically firmly attached. This heating is performed from one end of the flexible tube to the other end,
When the heat-shrinkable cylinder 5 is shrunk over the entire length of the tube to form the heat-shrinkable coating layer 2, the heating is completed.

At this time, it is preferable to use a heat source capable of annular heating or to rotate the heat source or the flexible tube being manufactured so that the entire circumference of the tube is evenly heated. In this example, heating is performed from one end of the tube to the other end, but heating may be performed from the center in the longitudinal direction of the tube to both ends.

In the above process, a thin braided braid 3 is formed on the outer surface of the synthetic resin tube 1 by the heat-shrinkable coating layer 2 over the entire length.
A flexible tube that was mechanically firmly attached and integrated with the synthetic resin tube 1, the thin-wire braided blade 3, and the heat-shrinkable coating layer 2 was able to be manufactured. In this embodiment, only by cutting the thin braided braid protruding from both ends of the flexible tube (for example, at the position of line AA in FIG. 1), specific use conditions (pressure,
Temperature, etc.).

In this case, since the flexible pipe uses the synthetic resin pipe 1 having the corrugated pipe section 6, the pipe can be easily bent, and the piping system can be easily constructed. 1
Even when an elongation force acts on the inner surface, the synthetic resin pipe 1, the thin braided braid 3, and the heat shrinkable coating layer 2 are integrally deformed. For this reason, the extension force is mainly absorbed by the slight extension deformation of the thin wire braid, and large extension in the length direction of the entire flexible tube is prevented.

If necessary, as shown in FIG. 1, an annular collar member 7 is mechanically fixed on the end portion of the thin braided braid mounted on the straight tube portion, and a cross section of the synthetic resin tube is formed. It is inserted until it comes into contact with the end of the corrugated tube 6 and fitted. In this case, after such fitting, the collar member is crimped and attached if necessary. Further, as the mechanical fixing means, a fixing means having a variable circumferential length, such as a screw type hose band, or other fixing means can be used.

In particular, when the thin wire braid is firmly attached to the end of the synthetic resin pipe, an annular groove or projection is provided on the outer circumference of the straight pipe section, and an annular projection or groove is provided on the inner circumference of the fixing means. May be provided, and the fixing means may be attached so that one convex portion is fitted into the other concave portion.

Then, the portion of the thin braided braid that protrudes from the collar member is cut, and these treatments are applied to the straight tube portions provided at both ends of the flexible tube, thereby completing the manufacture of the flexible tube.

Therefore, according to the present embodiment, in order to attach the thin wire braid blade 3 in close contact with the synthetic resin tube, the tubular thin wire braid blade 3 is extrapolated into the synthetic resin tube 1 and heat shrinkage is applied thereto. The tube 5 is extrapolated and the heat-shrinkable tube 5
It is easy to handle the thin wire braid blade 3 which is easily deformed, and the braid blade can be easily and firmly attached to the synthetic resin tube without causing slack in the thin wire of the braid blade. The flexible tube can be easily manufactured as a whole.

Further, the flexible tube 1 of the present embodiment can be easily bent since the synthetic resin tube 1 having the corrugated tube section 6 is used, so that the piping system can be easily constructed. The thin wire braided blade 3 is formed by the heat-shrinkable coating layer 2.
At the same time, it is mechanically firmly attached to the outer surface of the synthetic resin tube 1 and is integrated, so that even if the synthetic resin tube 1 receives an elongation force due to the internal pressure, the elongation force is slightly increased by the thin wire braided blade 3. It is absorbed by the elongation, and the elongation in the entire length of the flexible tube becomes small. In the present embodiment, the synthetic resin tube 1
Is provided with a straight pipe portion 4 at the end thereof, and the end portion of the thin wire braid blade 3 is fixed to the straight pipe portion 4 with a collar member. Therefore, the thin wire braid blade 3 can be more securely attached to the synthetic resin pipe 1. .

[0039]

As described above, according to the present invention, when a synthetic resin tube is used as an inner tube of a flexible tube, when a thin-wire braided blade is attached in close contact with the synthetic resin tube, the resin resin It is only necessary to extrapolate the tubular thin-wire braid to the tube, extrapolate the heat-shrinkable cylinder to these, and heat-shrink the heat-shrinkable cylinder 5 to cause slack in the fine-wire braid that is easily deformed. Therefore, the braided blade can be easily and firmly attached to the synthetic resin tube, and the flexible tube can be easily manufactured as a whole.

Further, since the flexible pipe of the present invention uses a synthetic resin pipe having a corrugated pipe section, the flexible pipe can be easily bent, and the piping system can be easily constructed. The blade is mechanically firmly attached to the outer surface of the synthetic resin tube with the heat-shrinkable coating layer by means of the heat-shrinkable coating layer. The force is absorbed by the slight elongation of the thin braided braid, and the effect is that the elongation of the flexible tube as a whole in the longitudinal direction is small.

[Brief description of the drawings]

FIG. 1 is a partial cross-sectional side view showing a part of a flexible tube according to an embodiment of the present invention.

FIG. 2 is a partially sectional side view showing a synthetic resin tube of the flexible tube shown in FIG.

FIG. 3 is a partial cross-sectional side view showing a state in which a thin braided braid is applied to a synthetic resin tube in a process of manufacturing the flexible tube shown in FIG.

FIG. 4 is a partial cross-sectional side view showing a state in which a thin braided braid is attached to a synthetic resin tube and a heat-shrinkable tubular body is attached to the synthetic resin tube in a process of manufacturing the flexible tube shown in FIG. .

FIG. 5 is a view showing a state in which a thin braided braid and a heat-shrinkable cylinder are applied to a synthetic resin tube in a process of manufacturing the flexible tube shown in FIG. 1, and the heat-shrinkable cylinder is heated. It is sectional side view.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Synthetic resin pipe 2 Heat-shrinkable coating layer 3 Fine-wire braided blade 4 Straight pipe part 5 Heat-shrinkable cylindrical body 6 Sectional corrugated pipe part 7 Mechanical fixing means (collar member)

Claims (4)

[Claims] 1. A tubular thin-wire braided blade (3) is extrapolated to a synthetic resin pipe (1) having a corrugated pipe section (6), and a heat-shrinkable tubular body (5) is extrapolated to these. The heat-shrinkable tubular body (5) is shrunk by heating, fastened to the synthetic resin pipe (1) to form a heat-shrinkable coating layer (2), and the thin wire braided blade (3) is connected to the synthetic resin pipe (1). A) a method for producing a flexible tube in which the outer surface is tightly coated. 2. The synthetic resin pipe (1) has a straight pipe section (4) at an end, and the end of the thin wire braided blade (3) is mechanically fixed to the straight pipe section (7). 4. The method for manufacturing a flexible tube according to claim 1, wherein said flexible tube is fixed to said step 4). 3. A synthetic resin tube (1) having a corrugated tube section (6), a heat-shrinkable coating layer (2) heat shrunk and applied to the synthetic resin tube (1), A flexible tube provided with a thin braided blade (3) which is in close contact with the outer surface of the resin tube (1) and is interposed between the synthetic resin tube (1) and the heat shrinkable coating layer (2). 4. A mechanical fixing means for providing a straight pipe part (4) at an end of the synthetic resin pipe (1), and fixing an end of the thin wire braided blade (3) to the straight pipe part (4). The flexible tube according to claim 2, comprising (7).