JPH0639122B2 - Method and apparatus for manufacturing synthetic resin mesh tube - Google Patents

Description

TECHNICAL FIELD The present invention relates to a method for producing a drainage pipe which is mainly buried in the ground and used for the purpose of absorbing and draining water, and an apparatus therefor, more specifically, suitable for absorbing and draining water. The present invention relates to a method and an apparatus for manufacturing a synthetic resin reticulated tube having a special mesh shape and having a strength capable of withstanding earth pressure.

(B) Conventional technology Conventionally, this type of drainage pipe is buried in the soil and collects water around the pipe to guide it to a predetermined place. Is required to have sufficient strength. It is widely known that the drainage efficiency of the synthetic resin mesh tube is closely related to the opening ratio of the mesh.

By the way, as a conventional drainage pipe, a drainage pipe made of synthetic resin having a simple mesh structure is used, and this type of drainage pipe was developed with thick vertical and horizontal strands in order to increase pressure resistance. There is.

In addition, in Japanese Utility Model Publication No. 51-38022, "reticulated tubular body made of synthetic resin"
A spirally wound reinforcing strand consisting of a strand that is thicker than the vertical and horizontal strands that make up the drain pipe is wound around the outer body of the drain pipe, and a drain pipe with a structure that substantially increases the pressure resistance of the mesh structure is used. Proposed.

(C) The problem to be solved by the invention However, in the former drainage pipe described above, when the thickness of the strand is made thicker, the openings are reduced, so that a sufficient suction and drainage effect cannot be obtained, and the weight of the drainage pipe increases. Therefore, there is a problem that workability is deteriorated, and conversely, if the thickness of the strand is made thin, it cannot withstand earth pressure.

In the latter drainage pipe, although the problem of pressure resistance was solved by the reinforcing strand, the problem remained in the mesh structure itself. That is, in the drainage pipe buried in the soil, even if the amount of rainfall is large, the rainwater that has penetrated into the soil is absorbed more stably than the mesh, and a rainwater flow path is created in the drainage pipe to reach a predetermined location. Since it serves as a guide, it is desirable that the mesh openings are large in order to obtain a high water absorption rate. But,
If the mesh is large, soil, sand grains, humus and the like will pass through the mesh and enter the drain pipe, which will cause a problem that the drainage function is deteriorated, and in the worst case, the drain pipe is clogged. On the other hand, if the mesh is made smaller, there is a problem that the mesh is clogged with earth and sand and water cannot be absorbed. In the conventional drainage pipes, the mesh openings are all rectangular, rhombic, and hexagonal in shape, and in particular, the opening at the top of the drainage pipe has a structure in which earth and sand easily enter.

The present invention has been made in consideration of the above circumstances, and provides a method and an apparatus for solving the above problems and manufacturing a synthetic resin reticulated tube having good drainage efficiency and high pressure resistance.

(D) Means and Actions for Solving the Problems This invention is a method for manufacturing a synthetic resin reticulated tube for manufacturing a tubular body composed of reticulated strands by extrusion molding, in which a large number of discharge holes are arranged in a ring shape at a predetermined pitch. In the inner nozzle for extruding the inner layer side strand formed, and in the outer nozzle for extruding the outer layer side strand, which is coaxially fitted around the inner nozzle and is formed with a large number of ejection holes arranged in a ring shape so as to closely correspond to the ejection holes. At least one of the nozzles is pendulum-moved with an arc length equal to or larger than the ejection hole arrangement pitch of the one nozzle as an amplitude, and each strand extruded from the pendulum-moving nozzle is meandered in a deep, substantially V-shape. Strands extruded from the nozzle are welded together to form a mesh with each other, and the entire structure is tubular.
A method for producing a reticulated tube made of synthetic resin, in which a second strand made of a strand sufficiently thicker than the strand of the reticulated tube is spirally wound around the outer body of the reticulated tube arranged in a tubular shape to obtain a tubular body, and , An inner nozzle for extruding the inner layer side strand, which is formed by arranging a large number of discharge holes in a ring shape at a predetermined pitch, and a plurality of discharge holes which are fitted coaxially around the inner nozzle and which are close to the discharge holes. The outer nozzles for extruding the outer layer side strands, which are arranged in an array, and at least one of the nozzles is pendulum-moved with an arc length equal to or larger than the discharge hole arrangement pitch as an amplitude, and each strand extruded from the pendulum-moving nozzle is formed into a deep V-shape Pendulum moving means for integrally forming a mesh-like strand by welding together with the strand extruded from the other nozzle in a state of meandering, And a means for arranging a reticulated strand protruding in a cylindrical or cylindrical shape on the extruding side to be extruded into a cylindrical shape, and a strand sufficiently thicker than the strand of the reticulated tube on the outer body part of the reticulated tube which is arranged in a cylindrical shape. Become second
Is a device for manufacturing a synthetic resin net-like tube, comprising a second nozzle for extruding the strand of No. 1 and spirally winding the strand, and a fusion resin supplying unit for supplying the fusion resin to each of the nozzles.

That is, according to the present invention, each strand extruded from one nozzle is meandered in a deep, substantially V-shape, is fused integrally with the strand extruded from the other nozzle, and is continuously formed in the extruding direction to form a complicated mesh. A reticulated tube with a shape is formed, and the outer body of the reticulated tube is wrapped with a second strand that is sufficiently thicker than the strand of the reticulated tube to reinforce it, thereby preventing clogging by soil and sand. It is possible to manufacture a reticulated tube that can be prevented, has excellent water permeability, and has high pressure resistance.

(E) Examples The present invention will be described in detail based on the examples shown in the drawings. The present invention is not limited to this.

First, referring to FIG. 1 to FIG. 3, a synthetic resin reticulated tube manufacturing method 1 includes a columnar center shaft 4 having an inner nozzle plate 2 and a mandrel 3, and a die having an outer nozzle plate 5 for accommodating the center shaft 4. 6, a first extruder 7 connected to the die 6, a drive device 8 for pendulum moving the center shaft 4, and a reinforcing strand winding device 9 as a second nozzle. 10
Is an extrusion flow path described later.

The most preferable thermoplastic resin applicable to the present invention includes polyethylene resin and polypropylene resin,
Not only these resins, but also so-called general-purpose plastics such as polyolefin, polystyrene, ABS resin, AS resin, PVC resin, methacrylic resin, and fluorine resin, nylon, saturated polyester resin, polycarbonate resin, polyarylate Engineering plastics represented by resins, polyacetal resins, polysulfones, modified polyphenylene ether resins and the like can also be applied.

Inner nozzle plate 2 for extruding inner layer side strand P ₁
Is an annular member mounted on the center shaft 4 by the bolts 11, and has a large number of discharge holes arranged in a ring shape at a predetermined pitch. Also, the outer strand P ₂
The outer nozzle plate 5 for pushing out is made of an annular member that is mounted on the die 6 by the bolt 12, is fitted coaxially around the inner nozzle plate 2, and corresponds to the discharge hole of the inner nozzle plate 2 in close proximity. A large number of discharge holes 5a are formed in a ring shape.

The die 6 accommodates the center shaft 4, and an extrusion flow path 10 for the molten resin is formed between the die 6 and the center shaft 4. The die 6 is supported by a die supporting means (not shown) including a die head and an adapter.

The mandrel 3 is composed of a tubular member screwed to the strand extruding side surface of the center shaft 4 and arranged to be cylindrical with the strands extruded from the discharge holes 2a, 5a of the inner nozzle plate 2 and the outer nozzle plate 5. is there. The extrusion molding machine 7 as the molten resin supply means supplies the molten resin to both nozzle plates 2 and 5 through the extrusion flow passage 10 so as to be extruded from the discharge holes 2a and 5a.

The drive device 8 as a pendulum moving means includes an arm 13 fixed to the center shaft 4, a disk 14 having an axis, a bar 15 for adjusting the distance between the arm 13 and the disk 14 and a turnbuckle 15a. Disc 14 to V-belt 16
Motor 17 for rotating through
Is rotated so that the arm 13 moves pendulum. The deflection angle is preferably set to 10 to 90 ° which corresponds to an arc length equal to or larger than the arrangement pitch of the ejection holes 5a, and a particularly preferable range is 20 to 70 °. The deflection angle can be changed as needed by adjusting the length of the bar 15 and by selecting the position of the mounting hole 14a of the disc 14. The turnbuckle 15a is for fine adjustment.

The reinforcing strand winding device 9 is for reinforcing a mesh tube formed of a strand sufficiently thicker than the strand on the outer body portion of the mesh tube P composed of the strands P ₁ and P ₂ extruded from both nozzle plates 2 and 5. It is for spirally winding the strand R in the axial direction of the reticulated tube P at a predetermined interval, and includes a spiral strand nozzle 18, a rotary die 19 for supporting the spiral strand nozzle 18, and a rotary die. It is mainly composed of a fixed die 21 supported via a thrust bearing 20, a sprocket gear 22 for rotating the rotary die 19, and an extrusion molding machine 23 for supplying the fused resin to the spiral strand nozzle 18.

The reinforcing strand R is not wound by utilizing the rotation of the reticulated tube which is the winding target. That is, since the reticulated tube is wound by rotating the rotary die 19 without rotating it, the winding direction does not follow the strand direction of the mesh as in the conventional case, but is independently wound. . Therefore, a reticulated tube which is not strong in one direction but a reticulated tube which is strong in various directions can be formed.

Although the spiral strand nozzle 18 has only one discharge hole in this embodiment, three strands R can be extruded by providing three discharge holes. In this case, the rotation speed of the rotary die 19 is 1 compared to the case where there is only one discharge hole
/ 3. Further, in this embodiment, the rotary die 19 is rotated so that the strand R is extruded only in one direction. However, another separate discharge hole is provided and the strand R in the crossed state is rotated by rotating in the opposite direction. Can also be wrapped around the mesh tube P. In addition, the extruders 7 and 2
3 can also be configured by one extruder, but when the reticulated tube P and the reinforcing strand R are composed of different resins, or the thickness of the reinforcing strand R is different from that of the reticulated tube P. It is preferable to use two extruders when it is desired to make the thickness much larger than the thickness.

Next, the operation of the synthetic resin reticulated tube manufacturing apparatus configured as described above will be described.

When the arm 13 moves pendulum due to the rotation of the motor 17, the inner nozzle plate 2 fixed to the center shaft 4 is moved to a position shown in FIG. 3a → FIG. 3b → FIG. 3c → FIG. 3b → FIG. When the molten resin is extruded from the discharge holes 2a and 5a through the extrusion channel 10 in this state, the pendulum moves continuously in the order of a, and the molten resin extruded from the discharge hole 2a has a deep V-shape. An inner layer side strand that meanders in a vertical direction is formed, and the substantially V-shaped inner layer side strand continuously penetrates in the extrusion direction in a state of intruding into a substantially V-shaped valley in the strand extruded from the adjacent discharge hole 2a. They are connected (see the shape of the strand on the inner surface side of the reticulated tube shown in Fig. 4a). The outer layer side strand, which is the fused resin extruded from the discharge holes 5a, is extruded in a straight line, but the portion that adheres to the inner layer side strand is drawn, so that it is in the opposite direction to the inner layer side strand, and A strand meandering in a V-shape shallower than the V-shape of the inner layer side strand is formed (fourth
(Refer to the outer pipe side strand shape shown in FIG. B). In this way, since the inner layer side strand and the outer layer side strand are formed in a substantially V shape having different depths and welded together, the mesh formed by both strands has a radial direction when viewed from the cross section of the mesh tube. (See FIG. 6b), but communicates with the inside of the reticulated tube at an angle. Therefore, it is constructed so that earth and sand cannot easily enter the mesh tube.

In addition, the outer nozzle plate 5 having the discharge holes 5a is attached to the discharge holes 2
It is also possible to move the pendulum in the opposite direction with respect to the inner nozzle plate 2 provided with a. In this case, the arrangement of the inner layer side strands and the outer layer side strands constituting the reticulated tube becomes regular, and the meandering amplitude is large. Therefore, the strength of the reticulated tube can be improved. However, in order to obtain a complicated mesh structure, it is preferable that the inner nozzle plate 2 and the outer nozzle plate do not have the same amplitude but the pendulums are moved with different amplitudes. In this case, in order to move the outer nozzle plate 5 as a pendulum, a sprocket gear (not shown) is attached to the outer periphery of the outer nozzle plate 5, and the sprocket gear is moved by using a drive device having the same configuration as in FIG. Just move it.

In the reticulated tube P thus obtained, the reinforcing strand winding device 9 further winds the reinforcing strands R around the outer body of the reticulated tube P, whereby the thick strands are spirally integrally fused. A braided tube is obtained.

The compressive strength of the reticulated tube increases due to the presence of the reinforcing strands R, but the compressive strength increases as the height of the reinforcing strands R in the radial direction increases. Of course, the cross-sectional shape of this reinforcing strand R is
It depends on the shape of the discharge hole. The shape of the discharge hole is preferably a circular cross section with high pressure resistance in various directions, but in addition, it may have a triangular, square, or elliptical cross section, or a hollow shape. Good.

Further, the thickness of the strands constituting the reticulated tube, taking a circular cross section as an example, the diameter of the reticulated tube in the range of 50 ~ 1000 mm, when the diameter of the inner layer side and the outer layer side strand is 1 ~ 5 mm thickness, The reinforcing strands have a diameter of 8 to 50 mm, the mesh openings are about 1 x 5 mm to about 2 x 10 mm, and the reinforcing strands have a winding pitch of 20 to 60 mm.

Further, in this embodiment, the reinforcing strand is composed of one line, but if a plurality of discharge holes, for example, three, are provided in the reinforcing strand winding device, the reinforcing strand composed of three lines can be extruded. According to the method, the rotation speed of the rotary die becomes ⅓, the pressure resistance of the reticulated tube can be increased, and the productivity of the reticulated tube can be improved. Further, the reinforcing strand has a larger winding pitch as the spiral winding angle becomes closer to vertical, and thus the pressure resistance increases.

When a rotary die provided with separate discharge holes is rotated in the direction opposite to the winding direction described above, sufficiently thick strands are formed in a state where they cross the outer body of the reticulated tube. Obtained from the tube.

FIG. 5 is a schematic side view of a synthetic resin reticulated tube production line for carrying out the present invention. In the figure, 30 is an extrusion molding machine, 31 is a raw material supply port, and 32 is an extrusion molding machine 30.
An adapter for connecting the first die with the first die, 33 a die for forming a mesh tube composed of meandering inner layer side strands and outer layer side strands, and 34 a die 3
3 is a center shaft, 35 is a drive device for reciprocally rotating the center shaft 34, 36 is a discharge hole of the die 33,
37 is a die for spirally winding a thick strand around the outer body of the mesh tube; 38 is a cooling device; 39 is a cooling water tank;
Is a caterpillar belt type reticulated tube taker, 41 is a cutting blade for cutting the reticulated tube to a predetermined length, and 42 is a reticulated tube finally obtained as a product.

FIG. 6a is a front view of a synthetic resin reticulated tube manufactured by the above manufacturing line, FIG. 6b is a right side view of FIG. 6a, and FIG. 6c is a DD arrow of FIG. 6a. FIG.

In this embodiment, the case where one type of resin is extruded from the extruder has been described, but as another embodiment, a polyethylene resin is used for the strands forming the reticulated pipe P, and a strand R for reinforcing the reticulated pipe is used. For example, the second extruding machine may be used to manufacture the reticulated tube by using two kinds of resins such as a resin having high rigidity such as polypropylene resin. The two types of resin used are
It may be appropriately selected depending on the application.

Further, the mesh of the reticulated tube composed of the inner layer side strand and the outer layer side strand has the diameter of the discharge hole of the inner nozzle plate 2 and the outer nozzle plate 5, the shape of the discharge hole, the inner nozzle plate 2
A mesh of various shapes can be obtained by independently and arbitrarily selecting the amplitude for moving the pendulum, the speed for moving the pendulum, and the like.

Furthermore, as indicated by the diagonal lines in FIG. 3a, the inner nozzle plate 2
If the outer nozzle plate 5 is provided with arc-shaped grooves (discharge holes) 2b, 5b over a length of about 1/4 to 1/2 of the entire circumference of the discharge hole side of the nozzle plate, it is molded. It is possible to form a non-hole portion (clogging state) in a band shape in about 1/4 to 1/2 of the entire circumference of the mesh tube. The strip-shaped non-perforated portion can completely prevent the invasion of earth and sand when the portion is positioned at the upper part when the mesh tube is buried, and when it is positioned at the lower part, it functions as a gutter and constitutes a smooth flow path. The thickness of the arcuate groove is preferably matched with the thickness of the discharge hole of the outer or inner nozzle plate.

(F) Effects of the Invention The present invention has a method and a structure for manufacturing a synthetic resin reticulated tube having a complicated opening shape for preventing clogging and integrally provided with a reinforcing strand for increasing pressure resistance. It is possible to provide a reticulated tube made of synthetic resin having high drainage efficiency and high pressure resistance.

[Brief description of drawings]

FIG. 1 is a plan view of an essential part showing an embodiment of a synthetic resin reticulated tube manufacturing apparatus according to the present invention, FIG. 2 is a perspective view of the same driving apparatus, and FIG. 4a is an explanatory view showing the inner shape of the reticulated tube, FIG. 4b is an explanatory view showing the outer shape thereof, and FIG. 5 is a schematic side view showing a synthetic resin reticulated tube production line, FIG. Figures 6b and 6
FIG. C is a front view, a right side view, and a cross-sectional view taken along the line D-D of the synthetic resin reticulated tube obtained from the production line. 1 apparatus for producing ...... synthetic resin mesh tube, 2 ...... inner nozzle, 5 ...... outer nozzle, 2a, 5a ...... discharge hole, P ₁ ...... inner side strand, P ₂ ...... outer layer strands, P ... … Reticulated tube, R… Second strand.

Claims (6)

[Claims] 1. A method for producing a synthetic resin mesh tube for manufacturing a tubular body made of mesh strands by extrusion molding, comprising an inner nozzle for extruding an inner layer side strand, in which a large number of discharge holes are formed in a ring shape at a predetermined pitch, and At least one of the outer nozzles for extruding the outer layer side strand, which is fitted coaxially around the inner nozzle and has a large number of discharge holes arranged in a ring shape in close proximity to the discharge hole, is The pendulum is moved with an arc length equal to or greater than the discharge hole array pitch as the amplitude, and each strand extruded from the pendulum moving nozzle is
In the state of meandering in a deep V-shape, the strand extruded from the other nozzle is integrally welded to form a mesh with each other, and the whole is arranged into a tubular shape. A method for producing a synthetic resin net-like tube, wherein a second strand, which is a strand sufficiently thicker than the strand of the net-like tube, is spirally wound around the tubular body to obtain a tubular body. 2. The outer body of the reticulated tube is wrapped around the outer body with two second strands crossing each other at a predetermined angle.
A method for producing the reticulated tube made of the synthetic resin described. 3. One of the nozzles is moved by a pendulum, the other nozzle is moved by a pendulum with an amplitude different from the amplitude of the one nozzle, and the substantially V-shaped depths of the strands extruded from the respective nozzles are changed to be integrated. The method for producing a synthetic resin reticulated tube according to claim 1, wherein welding is performed. 4. The method for producing a synthetic resin reticulated tube according to claim 3, wherein the outer layer side strand is formed by meandering in a substantially V shape deeper than the inner layer side strand. 5. A method for manufacturing a synthetic resin mesh tube for manufacturing a tubular body made of mesh strands by extrusion molding, wherein an inner layer for extruding an inner layer side strand in which a large number of discharge holes are arrayed at a predetermined pitch on the circumference. An outer nozzle for extruding an outer layer side strand, which is fitted coaxially around the nozzle and / or the inner nozzle and has a large number of discharge holes arranged on the circumference so as to closely correspond to the discharge hole, and the entire circumference of the nozzle. An arc-shaped groove is provided over a length of about ¼ to ½ of at least one nozzle, and at least one nozzle is moved as a pendulum with an arc length equal to or larger than the discharge hole arrangement pitch of the one nozzle as an amplitude, and a pendulum is moved. Each strand extruded from the discharge hole of the nozzle is welded together with the strand extruded from the discharge hole of the other nozzle in a state of meandering in a deep V-shape to form a mesh with each other. The synthetic resin extruded from the arc-shaped groove makes about 1/4 to 1/2 of the entire circumference of the mesh into a band shape, and the whole is arranged in a tubular shape. A method for producing a reticulated tube made of synthetic resin, wherein a second strand, which is a strand sufficiently thicker than the strand of the tube, is spirally wound around the tube to obtain a tubular body. 6. An inner nozzle for extruding a strand on the inner layer side, which is formed by arranging a large number of discharge holes in a ring shape at a predetermined pitch, and a large number of nozzles which are fitted coaxially around the inner nozzle and closely correspond to the discharge holes. Outer nozzles for extruding outer layer side strands formed by arranging discharge holes in a ring shape, and pendulum movement of at least one nozzle with an arc length equal to or larger than the discharge hole arrangement pitch as an amplitude, and each strand extruded from the pendulum moving nozzles. A pendulum moving means for forming a net-like strand by integrally welding with a strand extruded from the other nozzle in a state of meandering in a deep V-shape, and extruded from the inner nozzle in a cylindrical or cylindrical shape protruding toward the strand extruding side. The means for arranging the reticulated strand into a cylindrical shape and the outer body of the reticulated tube arranged in a cylindrical shape are An apparatus for manufacturing a synthetic resin reticulated tube, comprising a second nozzle for extruding a second strand composed of a large strand and spirally winding the second strand, and a fusion resin supplying means for supplying a fusion resin to each nozzle. .