JPS59210115A - Plastic drain pipe of reticular structure - Google Patents

Abstract

PURPOSE:To obtain a reticular culvert having a high strength to external pressure by a method in which synthetic resin vertical wires are set in a circular form at intervals, their facing portions are partly bound, and the periphery of the circular vertical wires is wound with spiral synthetic resin bands of a T- shaped cross section. CONSTITUTION:Plastic vertical tubular wires 1 are set in parallel in a circular form at intervals (a), and a small number of the facing vertical wires 9 set circularly are contacted with each other. The lowest part of plastic spiral bands 2 of a T-shaped cross section is welded to the vertical wires 1 and 9 set circularly with a spacing (b) between the heads of the adjacent spiral bands 2. The deformation strength in the radial direction can be raised, the flexibility in the vertical direction can be lowered, and the flexibility in the horizontal direction can also be raised.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a plastic mesh drain pipe that is buried in soil or the like and used to guide water flowing in from the surroundings to a culvert or the like.

This type of drainage pipe not only has good water collection and circulation properties, but also has the strength to avoid being compressed by soil pressure, vehicle wheel pressure, etc. during handling and after burial, and it also needs to be flexible. In particular, when buried, it is necessary to have directional strength characteristics such as sufficient bending resistance in the vertical direction and easy bending in the horizontal direction.

However, as conventional plastic mesh pipes, utility model application publication No. 16901/1982 and published patent application No. 1983
The materials described in JP-A-154137 and the like have low crushing strength and do not have the above-mentioned directional strength characteristics. If the strength is simply to be increased, the striations that intersect vertically and horizontally or diagonally forming the reticular tube may be made thicker, but this not only reduces the mesh size and causes clogging, but also reduces flexibility. Therefore, forming a drainage pipe by connecting a ready-made bent pipe to the bent part increases the number of man-hours and the types of bent pipes are limited, so it is the most economical way to form a drainage pipe according to the burial site. cannot be formed. Further, in the conventional example described above, in order to increase the flexibility, 1ljl 11 is increased, which results in a decrease in strength and also causes clogging due to the intrusion of sand and gravel in the soil.

An object of the present invention is to provide a plastic mesh drain pipe that solves the various problems mentioned above.

In the present invention, a plastic mesh drainage pipe is placed on the outside of a large number of vertical plastic lines arranged in parallel at intervals along the generatrix of the pipe, and is made of plastic with a T-shaped cross section. ! The bases of the riflings are joined together so that the heads of the IIf riflings are spaced apart to form a mesh drainage pipe, and if necessary, a small number of longitudinal striations are added to the opposite sides of the narrow drainage pipe. By making them come into contact with each other, it is possible to bend downwardly under -L in the buried state, and it is easy to bend horizontally.

Hereinafter, the embodiments of the present invention will be described. Reference numeral 1 denotes plastic tubular vertical filaments arranged in parallel along the generatrix of the tube with an interval a, and numeral 2 denotes a cross-section of T, which is joined to the outside of these vertical filaments.
A helical strip joins the base 4 of the T-shaped section to the longitudinal strip 1 such that the head 3 of the T-shaped section has a gap. Therefore, the distance C between the bases 4 is much larger than the distance between the heads,
While the interval C is made small to prevent the intrusion of sand and gravel, the interval a,
The mesh 5 formed by c has a large area and is prevented from being clogged with earth and sand.

The cross-sectional shape of the spiral strip 2 is basically a square Gothic shape (a) shown in FIG. (b) or rail shape fc), and in reality, the shape will be somewhat different from the above shape depending on the molding method described later.

- The mesh drainage pipe with the structure described in
Because the width of the pipe 8 is small and the joint area with each vertical line 1 is small, and the head 3 is wide but forms a spiral line, the resistance to bending as a whole is small and bending piping is easy. On the other hand, the vertical legs 8 exhibit strong resistance against the force that crushes the mesh drain pipe.

Therefore, the mesh drain pipe of the present invention is strong and has high flexibility.

Furthermore, when a small number of vertical filaments 1 on opposite sides of the mesh drain pipe are brought into contact with each other to form a strip portion 9.9, and this mesh drain pipe is buried with the strip portion 9.9 horizontally, , the bending strength in the vertical direction is strong, and the downward deflection due to tonosho etc. is reduced.

Therefore, the inconvenience that dirt accumulates on the downwardly bent portion and impedes water flow is eliminated, and moreover, it maintains good flexibility in the horizontal direction.

FIG. 4 shows an example of the method for manufacturing the reticulated drain pipe of the present invention. From a die (not shown), the thick-walled cylindrical portion 10 that becomes the spiral strip 2 and the perforated comb-toothed portion 11 that protrudes inward and becomes the vertical strip 1 are extruded together with a diameter larger than that of the mesh drainage pipe, or as separate parts. After extruding them, they are fused together, and while being pulled to the right by a take-up roller (not shown), they are moved along the surface of the torpedo 12 corresponding to the inner diameter of the mesh drainage pipe. It is cooled from within by jetting cold air. The cylindrical part 1 is now in a semi-molten state.
A thin blade 15 of a rotary cutter 14 rotating in a direction perpendicular to the axis of the torpedo 12 is cut into the torpedo 12 to cut the cylindrical portion 10 into spiral strips.

Rotary cutter 14, each T-shaped spiral strip 2 shown in Fig. 3 a, b, c
5, 6, and 7, respectively. That is, for the T-shaped spiral strip shown in FIG. 3a, as shown in FIG. is provided, and the semi-molten cylindrical portion 10 is canted into a spiral strip, and the cut resin on both sides is scooped up by scraping blades 16 to form a T-shaped volume space 18. In this case, the scooped-up resin forms the head 3 of the spiral strip 2, and is cooled and solidified while the distance between the Wi parts gradually increases due to the above-mentioned withdrawal. Since the head 3 is formed as described above, its cross-sectional shape is not a precise square Gothic shape, but is approximately T-shaped with rounded corners. The notch 17 introduces air from behind between the cutting surfaces of the cutting blade 15 to facilitate the cutting.

The rotary cutter 14 shown in FIG. 6 has ears 19 rising diagonally upward on both sides of the scraping blade 1G, thereby forming a downward protrusion 6. Further, the rotary cuck 14 in FIG. 7 corresponds to the rake W2O in FIG. 5 shifted in two directions.

The spiral strips 2 formed in two sets are cooled from the outside by a rotary cutter 14 to continuously form a mesh drain pipe.

The present invention has the above-mentioned configuration, and has strong deformation strength in the radial direction with respect to tonosho etc. due to the spiral striations having a shape of ゛ in cross section, and also prevents the intrusion of sand and gravel. Even if the spacing between the spiral strips is narrowed to prevent the r - Although it is difficult to bend downward,
It is easy to bend in the horizontal direction, and therefore has remarkable effects such as preventing water flow from being obstructed by dirt accumulated in bent parts due to landslides, etc., and making it easy to meander horizontally.

[Brief explanation of drawings]

Fig. 1 is a cross-sectional view of one embodiment of the present invention, Fig. 2 is a partial perspective view, and Fig. 3 a, b, and c are IJ! Various cross-sectional views of I rifling,
Fig. 4 is a perspective view of the main parts showing the manufacturing method, Fig. 5, Fig. 6,
Figure 7 is Figure 3a, respectively. The rotary cutter corresponding to b and c is shown;
The mouth is an elevation view, and the side view is side view. 1... Vertical striations 2... Spiral striations 3... Head 4
...Basic agent Patent attorney Yuyosuke - 1 other person

Claims (2)

[Claims] (1) The base of a roughly 1゜-shaped plastic spiral strip is joined to the outside of a large number of plastic vertical strips arranged parallel to each other at intervals along the generatrix of the pipe, such that the heads of the spiral strips are spaced apart from each other. A plastic mesh drain pipe. (2) A large number of plastic vertical filaments are arranged in parallel at intervals along the generatrix of the tube, with a small number of vertical filaments touching each other on opposite sides of the tube, and the outer side of the vertical filaments is approximately T-shaped. A plastic mesh drain pipe formed by joining the bases of cross-sectional plastic spiral strips so that the heads of the spiral strips are spaced apart.