JPH09264461A - Corrugated pipe - Google Patents

Abstract

PROBLEM TO BE SOLVED: To facilitate the piping work of a corrugated pipe useful as a protection pipe at the burying time of a cable under the ground and reduce a piping expenses. SOLUTION: The rolling of a pipe at the installation time on the ground G is prevented and the pipes can be piled and collected without using a pipe stand by making the outer periphery of a projection part 3 formed on the peripheral surface of the pipe main body 2 of a corrugated pipe 1 in a polygon shape.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a corrugated pipe used as a protective pipe when a cable such as an electric wire or a communication line is buried underground.

[0002]

2. Description of the Related Art Conventionally, a corrugated tube (11) as shown in FIG. 7 has been used as a cable protection tube. The corrugated tube (11)
Is formed on the peripheral surface of the pipe body (12) along the axial direction with a large number of convex portions (13) having a circular outer periphery, and the rib effect of the convex portions (13) makes it possible to withstand earth pressure. It was done.

[0003]

The corrugated pipe (11) has a convex portion.
Since the outer circumference of (13) is circular, it is unstable even if it is installed on the ground. In addition, a pipe stub is required to bundle multiple pipes, which requires time and effort for piping work, and the piping cost is high. There was a problem that it would be too high.

[0004]

As a means for solving the above-mentioned conventional problems, the present invention provides a polygonal outer circumference on a circumferential surface of a tube main body (2) having a circular cross section at predetermined intervals along the axial direction. The corrugated tube (1) is provided with a large number of convex portions (3). It is desirable to insert an inner tube (4) having a circular cross section inside the tube body (2) of the corrugated tube (1) so as to be in close contact with the tube body (2).

[0005]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention is shown in FIGS. In the corrugated pipe (1) shown in the figure, (2) is a pipe main body having a circular cross section, and the peripheral surface of the pipe main body (2) has straight corners at predetermined intervals along the axial direction. A large number of convex portions (3) each having a rectangular chamfered outer circumference are formed. An inner pipe (4) having a circular cross section is inserted inside the pipe body (2) so as to be in close contact with the pipe body (2), and the inner pipe (4) is attached to the pipe body (2).
It may be fused with the tube body (2) at the valley portion (5) between the convex portions (3).

The corrugated pipe (1) having the above structure can be stably installed on the ground G without rolling, as shown in FIG.
Further, as shown in FIG. 4, a plurality of corrugated pipes (1) can be stacked and focused by superposing the sides of the convex portions (3) on each other without a nozzle.

When the corrugated pipe (1) is buried in the ground,
Since the outer circumference of (3) is quadrangular, it receives earth pressure perpendicular to the surface on its side, but since the pipe body (2) has a circular cross section, the earth pressure acts in the normal direction, and therefore the corrugated pipe (1) can withstand earth pressure, but in this example, the pipe body
Since the inner tube (4) is inserted inside (2), the corrugated tube
The earth pressure resistance strength of (1) is further improved by the inner pipe (4). Furthermore, the inner pipe (4) is a trough (5) of the pipe body (2).
In the case of being fused with the pipe main body (2), it is prevented that the convex portion (3) of the pipe main body (2) is crushed by the earth pressure, and the rib effect of the convex portion (3) is effective. Working strength of the corrugated pipe (1) is further improved. The body of the corrugated pipe (1)
Even if (2) is damaged, the entry of earth and sand and water is blocked by the inner pipe (4). Further, when inserting a cable into the corrugated tube (1), the corrugated tube (4) must be inserted unless the inner tube (4) is inserted.
Although the tip of the cable is easily caught in the inner corrugation of (1), it becomes difficult to insert the cable, but since the inner pipe (4) conceals the inner corrugation, such a problem is solved in this example.

In the above-mentioned specific example, the convex portion (3) of the pipe body (2) has a quadrangular outer circumference whose corners are chamfered linearly.
Convex part formed on the pipe body (2A) like the corrugated pipe (1A) shown in
(3A) may have a quadrangular outer periphery with a corner chamfered in a curved shape, and as shown in FIG. 6, a corrugated pipe (1B) pipe main body
The outer peripheral shape of the convex portion (3B) formed in (2B) may be a hexagon, or may be another polygonal shape such as a triangle.

[0009]

According to the present invention, since the outer periphery of the convex portion (3) of the corrugated pipe (1) is polygonal, it is stable without rolling when the corrugated pipe (1) is installed on the ground. And, since the stacking and focusing can be performed without using the nozzle, the piping work is facilitated and the piping cost is reduced.

[Brief description of drawings]

 1 to 4 show a specific example of the present invention.

FIG. 1 is a partial perspective view.

FIG. 2 Partially cutaway side view

[Fig. 3] Front view of installation state

FIG. 4 is a front view of a stacking and focusing state.

FIG. 5 is a front view of another specific example.

FIG. 6 is a front view of yet another specific example.

FIG. 7 is a perspective view of a conventional example.

[Explanation of symbols]

 1,1A, 1B Corrugated tube 2,2A, 2B Tube body 3,3A, 3B Convex section 4 Inner tube

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Tadanobu Suzuki 74 Aron Kasei Co., Ltd. Technical Research Institute, 1 Funami-cho, Minato-ku, Nagoya, Aichi (72) Inventor Masa Hasegawa, Funami-cho, Minato-ku, Nagoya, Aichi No. 74 Aron Kasei Co., Ltd. Technical Research Center

Claims (4)

[Claims] 1. A corrugated pipe characterized in that a large number of convex portions having a polygonal outer periphery are formed on a peripheral surface of a pipe main body having a circular cross section along an axial direction at predetermined intervals. 2. The convex portion has a square outer periphery.
Corrugated tube described in 3. The corrugated tube according to claim 2, wherein the convex portion has a quadrangular outer circumference whose corner portions are chamfered linearly or curvedly. 4. The corrugated pipe according to claim 1, wherein an inner pipe having a circular cross section is inserted inside the pipe body so as to be in close contact with the pipe body.