JPS5920412Y2 - culvert pipe - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an underdrain pipe that improves drainage of playgrounds, etc.

In sports fields, tennis courts, fields, cultivated land, etc.
Underground pipes are buried underground to improve water drainage, but conventional pipes simply have a hole in the cylindrical pipe and cover the outside with a filter, allowing water to enter the pipe from outside through the hole. Therefore, the filter is easily compressed by the outer periphery of the pipe and the surrounding soil, causing clogging, and the filter itself blocks the flow of water, making it difficult for water to flow into the pipe.

Therefore, the applicant developed a pipe in which the outer periphery of the pipe has irregularities to form a space between the outer periphery of the pipe and the filter to improve the flow of water, but there were difficulties in terms of strength and manufacturing. .

The present invention has been made in view of the above points, and aims to provide an underdrain pipe that has good water drainage, is easy to manufacture, and has increased strength.

The underdrain pipe according to the present invention has a cylindrical resin pipe body with a plurality of annular ribs at regular intervals in the axial direction, and an annular bottom wall is formed in the part where the annular ribs are not formed. Notches are provided at opposite positions in the diametrical direction of the annular rib, the notches are formed approximately perpendicular to the plane passing through the axis of the pipe, and a hole is bored in the bottom wall, The outer periphery of the pipe body is covered with a filter.

Therefore, soil water passes through the filter, first enters between the annular ribs, and then flows into the interior of the pipe body through the holes in the bottom wall.

The cutout allows the water passing through the filter to flow in the axial direction.

In the underdrain pipe according to the present invention, an annular rib, a notch, and a hole are formed in the pipe body, and then the filter is covered, so for example, after extrusion molding, blowing or suction is performed to create the annular rib, and then the notch is press-molded. However, manufacturing is simple because the bottom wall only needs to be made by drilling.

In addition, sufficient strength can be maintained by the annular rib.

And since the notches are located at opposite positions in the diametrical direction,
In addition to preventing a decrease in strength, water flows smoothly through the notch because the notch is located at least half the diameter of the pipe body regardless of the installation state of the underdrain pipe.

Further, since the notch is formed in a direction substantially perpendicular to the plane passing through the axis of the pipe, continuous manufacturing using a mold is easy.

In particular, according to the present invention, a relatively narrow space is created between the filter and the bottom wall between the annular ribs, so that the small holes are not blocked by the filter.

Furthermore, although the filter is slightly bent into the space due to soil pressure and water pressure, it actually blends better with the surrounding earth and sand, and the underdrain pipe does not move in the axial direction.

Even if a partial blockage were to occur, the water would flow smoothly overall.

Therefore, according to the present invention, it is possible to obtain an underdrain pipe that is strong and easy to manufacture, and also allows water to flow in and out in an extremely suitable manner.

An embodiment of the underdrain pipe of the present invention will be described below.

In the figure, the underdrain pipe is formed by protruding from a cylindrical synthetic resin pipe body 1 a large number of annular ribs 2 extending in the circumferential direction.

The large number of annular ribs 2 are spaced apart from each other at regular intervals in the axial direction of the pipe, and therefore, the portion where the annular ribs 2 are not formed forms an annular bottom wall 3.

Each annular rib 2 has one to three, preferably two, notches 4a.

4b are provided in pairs only at positions facing each other in the diametrical direction.

The formation of the annular rib 2 and the notches 4a and 4b described above is performed as shown in Japanese Patent Publication No. 58-12851, for example.
This is done using endless segmented molds placed one above the other.

Such upper and lower molds open and close in a direction perpendicular to a plane passing through the axis of the pipe.

Therefore, in order to adapt to the opening and closing of the split mold,
The notch opens in a direction substantially perpendicular to a plane passing through the axis of the pipe body 1.

The bottom walls 5 of the notches 4 a and 4 b are flush with the bottom wall 3 of the pipe body or are slightly higher than the bottom wall 3 .

Holes 6 are appropriately bored in the bottom wall 3. In addition, notch 4
It is preferable that a and 4b form a chamfer 4C, and the width of the small bouf formed by adjacent notches 4a and 4b is larger than the width of notches 4a and 4b, and It is preferable that the notches 4a or 4b be made in a zigzag pattern, that is, staggered in the axial direction of the pipe body, so that when the pipe is viewed in the axial direction, the notches 4a or 4b are in a continuous state and cannot be seen. 2
better retained.

This filter 8 allows substantially only liquid to pass through, and its construction may include a synthetic resin net, synthetic or natural fiber steel, woven fabric, non-woven fabric, or foam-molded or foam-molded sheet. A plate or cylinder, etc., in which small holes are formed by bursting the air bubbles of the sheet material, and the holes are mechanically perforated in the sheet-like material.
A combination of these is preferred.

For example, when the bubbles in the foam sheet are burst, the small pores of the filter 8 are 0.1 to 5 mm, preferably 1 to 5 mm.
Conveniently, it has a diameter of about 2 mm.

In order to cover the pipe with these filters 8, they may be simply wrapped over the pipe, or they may be fixed to the pipe.

Furthermore, if both the protrusion and the filter are made of synthetic resin, they can be thermally welded when or after covering the filter, making manufacturing, construction, and maintenance easier and more reliable.

The underdrain pipe according to the present invention is constructed as described above, and when used underground, filters can be filtered between the annular ribs and notches formed on the pipe body at regular intervals in the axial direction. Since a space is formed between ・ and the bottom wall, water flows well through this space, and further flows well from the hole 6 or from the connecting end of the pipe body 1 to the central ρ space of the pipe body. Water drainage will be carried out.

Furthermore, since the notches are provided only at positions facing each other in the diametrical direction of the annular rib, the annular rib effectively exerts a reinforcing effect, increasing the strength of the pipe itself.

In addition, since the notch is formed in a direction approximately perpendicular to the plane passing through the axis of the pipe, it is suitable for continuous manufacturing using an endless mold that opens up and down, increasing production efficiency and improving production efficiency. Costs can be reduced.

[Brief explanation of the drawing]

The figure shows an example of an underdrain pipe according to the present invention.
FIG. 1 is a perspective view thereof, and FIG. 2 is a side view partially shown in section. 1... Pipe body, 2... Annular rib,
4 a, 4 b...notch.

Claims (1)

[Scope of utility model registration request] A large number of annular ribs are formed on the cylindrical synthetic resin pipe body at regular intervals in the axial direction, and an annular bottom wall is formed in the part where the annular ribs are not formed, and each annular rib is diametrically opposed to each other. A notch is provided at the position where the pipe body is located, this notch is formed approximately perpendicular to the plane passing through the axis of the pipe, a hole is bored in the bottom wall, and the outer periphery of the pipe body is provided with a filter. An underdrain pipe characterized by being covered.