Cylindrical permeable material

Abstract

To provide a cylindrical water-permeable material that can reduce the amount of monofilament used and the manufacturing costs, and has sufficient tensile strength and compressive strength, and a manufacturing method thereof.SOLUTION: A cylindrical water-permeable material 1 has a cylindrical shape as a whole and is composed of monofilament rolls 2a to 2d stacked in the radial direction. Each of the monofilament rolls 2a to 2d is formed into a cylindrical shape in a state in which a plurality of synthetic resin monofilaments 11 are randomly curved or bent in three-dimensional directions and entangled, and have a large number of continuous voids inside. In this cylindrical water-permeable material 1, a water-permeable sheet 3 is disposed between two stacked monofilament rolls 2b and 2c.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a water-permeable material that is buried in the ground to discharge water infiltrated into the ground by rainfall or spring water in the ground to the outside, or is used for drainage on slopes, slopes, etc., and a method for manufacturing the same.

Background Art

[0002] In a drainage device buried in the ground for the purpose of discharging infiltrated water and spring water in the ground to the outside, in order to prevent foreign substances from entering the drainage device and secure a space serving as a drainage path, a water-permeable material having a large number of continuous voids is arranged in the drainage device.

[0003] There are various types of water-permeable materials to be installed in the drainage device. For example, a material in which a plurality of synthetic resin monofilaments are randomly curved or bent in three-dimensional directions and intertwined to be integrated in a state having continuous voids inside is known.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0005] When manufacturing a water-permeable material by randomly curving or bending multiple monofilaments, it is not particularly difficult to form it into a plate or sheet shape with a thickness of about 10 to 30 mm. However, when attempting to manufacture a rectangular bar-shaped water-permeable material with widths and heights of about 70 to 100 mm, for example, to match the size of the cross-section of a drainage channel in a drainage system (a cross-section perpendicular to the longitudinal direction), by curving or bending multiple monofilaments, there is a problem in that the weight of the upper layer compresses the lower layer, resulting in an unnecessarily high density in the lower layer. This leads to an increase in the amount of monofilaments used (i.e., the amount of synthetic resin raw material used), and thus an increase in manufacturing costs.

[0006] The present invention aims to solve the problems of the prior art described above, and to provide a cylindrical water-permeable material that can reduce the amount of monofilament used and the manufacturing cost, as well as a method for manufacturing the same. [Means for solving the problem]

[0007] The cylindrical water-permeable material according to the present invention is characterized by having an overall cylindrical shape and being composed of two (three or four or more) monofilament rolls stacked radially, in which multiple monofilaments made of synthetic resin are randomly curved or bent and intertwined in a three-dimensional direction, and are formed into a cylindrical shape with a large number of continuous voids inside.

[0008] Furthermore, in this cylindrical water-permeable material, it is preferable that a water-permeable sheet is placed between two stacked monofilament rolls.

[0009] The present invention provides a method for manufacturing a cylindrical water-permeable material, comprising: preparing at least two lines for manufacturing a flat primary molded product having continuous voids inside, by randomly curving or bending multiple monofilaments of synthetic resin with a diameter of 1 to 3 mm, extruded from an extrusion molding machine, in a three-dimensional direction to entangle them with each other; and providing a roll processing device having a winding shaft connected to the drive shaft of a motor and configured to rotate in a predetermined direction by the driving force of the motor; supplying the primary molded product manufactured by one line to the winding shaft at an angle and winding it spirally around the outside of the winding shaft to form the first monofilament roll; and supplying the primary molded product manufactured by the other line to the winding shaft at an angle and winding it spirally around the outside of the first monofilament roll to form the second monofilament roll.

[0010] Furthermore, the roll processing apparatus used in this method has a side edge guide that contacts the side edge of the supplied primary molded product and guides the primary molded product in a spiral direction, and an outer guide that presses the supplied primary molded product from the radially outside of the winding shaft, the side edge guide has a spirally curved shape and is arranged and fixed so as to surround the outside of the winding shaft and contacts the side edge of the supplied primary molded product and is configured to guide the primary molded product in a spiral direction on the outside of the winding shaft, and the outer guide is a trough Preferably, the device has a curved shape and is positioned and fixed at a certain distance from the outer surface of the winding shaft so as to partially surround the winding shaft, and is configured to press the supplied primary molded product from the radially outside of the winding shaft. Preferably, the primary molded product is supplied so that its side edges follow the side edge guides, and is driven into the gap between the outer guide and the winding shaft, or the gap between the outer guide and the inner monofilament roll, to perform the winding.

[0011] Furthermore, it is preferable to place a line for supplying a water-permeable sheet between any two of the lines that manufacture primary molded products, wrap the water-permeable sheet around the outer surface of a monofilament roll formed by primary molded products supplied from one line, and then wrap the primary molded product supplied from the other line around the outside of that, thereby placing the water-permeable sheet between the two stacked monofilament rolls.

[0012] Furthermore, it is preferable to position a feed roller so that it can contact the outer surface of the monofilament roll, and to supply driving force to the feed roller to rotate it in a predetermined direction, thereby feeding the molded product toward the tip of the winding shaft. [Effects of the Invention]

[0013] The cylindrical permeable material according to the present invention can be manufactured by an extremely simple method, and the amount of synthetic resin raw material used can be reduced, thereby lowering manufacturing costs. Furthermore, the manufacturing method of the cylindrical permeable material according to the present invention can be expected to improve the tensile strength and compressive strength of the molded monofilament.

[0014] Furthermore, by placing a permeable sheet between two stacked monofilament rolls, it is possible to prevent foreign matter (gravel, sand, soil, etc.) from entering the center of the cylindrical permeable material, and it is also expected that the rigidity of the cylindrical permeable material will be improved. [Brief explanation of the drawing]

[0015] [Figure 1] Figure 1 is a cross-sectional view of a cylindrical water-permeable material 1 according to the first embodiment of the present invention. [Figure 2] Figure 2 is a partial enlarged view of a single monofilament 11 that constitutes the cylindrical water-permeable material 1 shown in Figure 1. [Figure 3] Figure 3 is an explanatory diagram of a method for manufacturing a cylindrical water-permeable material according to the second embodiment of the present invention, and is a perspective view of the extrusion molding machine 71 and conveyor 81, etc. [Figure 4]FIG. 4 is a diagram showing the structure on the lower surface side of the die 72 shown in FIG. 3. [Figure 5] FIG. 5 is a diagram showing an example of the shape of the monofilament 11 supplied and conveyed on the conveyor 81. [Figure 6] FIG. 6 is a side view of the extrusion molding machine 71 shown in FIG. 3 and the like. [Figure 7] FIG. 7 is a plan view of the roll processing apparatus 61 used in the method for manufacturing a cylindrical water permeable material according to the second embodiment of the present invention. [Figure 8] FIG. 8 is a diagram showing a vertical cross section of the winding shaft 62 taken along the X-X line shown in FIG. 7, and side views of the side edge guide 64 and the outer guide 65. [Figure 9] FIG. 9 is an explanatory diagram of the method for manufacturing a cylindrical water permeable material according to the second embodiment of the present invention. [Figure 10] FIG. 10 is an explanatory diagram of the method for manufacturing a cylindrical water permeable material according to the second embodiment of the present invention. [Figure 11] FIG. 11 is an explanatory diagram of the method for manufacturing a cylindrical water permeable material according to the second embodiment of the present invention. [[ID=?]] [Figure 12] FIG. 12 is an explanatory diagram of the method for manufacturing a cylindrical water permeable material according to the second embodiment of the present invention. [Figure 13] FIG. 13 is an explanatory diagram of the method for manufacturing a cylindrical water permeable material according to the second embodiment of the present invention.

Embodiments for Carrying Out the Invention

[0016] The present invention can be implemented as a "cylindrical water permeable material" and can also be implemented as a "method for manufacturing a cylindrical water permeable material". Hereinafter, each embodiment of the present invention will be described with reference to the accompanying drawings.

[0017] (First Embodiment: Cylindrical Water Permeable Material) It should be noted that there seems to be a problem with the numbering in the original text. The "[[ID=?]]" is likely an error in the original numbering. I have translated it as is while pointing out this potential issue.Figure 1 is a cross-sectional view of a cylindrical permeable material 1 according to the first embodiment of the present invention. As shown in the figure, the cylindrical permeable material 1 has an overall cylindrical shape and is composed of four layers of monofilament rolls 2a to 2d stacked in the radial direction and a permeable sheet 3 placed in the middle. However, the permeable sheet 3 may be omitted depending on the usage conditions and application (the cylindrical permeable material 1 may be composed only of the four layers of monofilament rolls 2a to 2d).

[0018] The monofilament rolls 2a to 2d are each formed into a cylindrical shape from multiple synthetic resin monofilaments 11 (diameter 1.5 to 2.5 mm, preferably 2 mm) that are randomly curved or bent in a three-dimensional direction and intertwined, resulting in a state where there are many continuous voids inside. In this embodiment, the thickness of the monofilament rolls 2a to 2d is set to 15 mm, but it can be appropriately set within the range of 10 to 30 mm. The water-permeable sheet 3 is made of a water-permeable synthetic resin nonwoven fabric (thickness 0.2 mm).

[0019] Figure 2 is an enlarged view of a single monofilament 11 that constitutes the cylindrical water-permeable material 1 shown in Figure 1. As shown, the surface of the monofilament 11 has numerous small irregularities with a height or depth of about 0.1 to 0.5 mm, and the entire surface is not smooth but rather has a rough surface.

[0020] The cylindrical permeable material 1 in this embodiment has a diameter of approximately 160 mm, but is not limited to this dimension. Similarly, there are no particular limitations on its length; it can be any length. For example, it can be approximately 1 to 4 m for easy handling, or it can be 10 m or more if necessary.

[0021] This cylindrical permeable material 1 can be housed in a trough-shaped plastic case to constitute a drainage system. In this drainage system, the enclosed cylindrical permeable material 1 reduces the resistance to water flow within the trough-shaped case, allowing for rapid drainage of seeping water. Furthermore, even when this drainage system is placed underground, it can withstand soil pressure without problems, and a permanent drainage path (continuous space) can be secured within the trough-shaped case. When housing this cylindrical permeable material 1 in a trough-shaped case, it is preferable to place a permeable mesh sheet (nonwoven fabric, etc.) on top of the cylindrical permeable material 1 to prevent the intrusion of foreign matter such as gravel, sand, and soil.

[0022] Furthermore, by not using a trough-shaped case or the like, and covering the lower and left and right sides of the cylindrical permeable material 1 with a waterproof sheet, it is possible to construct a drainage device with a simpler structure.

[0023] In this embodiment, the cylindrical permeable material 1 is composed of four monofilament rolls 2a to 2d and a permeable sheet 3 placed in between. However, it is also possible to arrange one or more monofilament rolls outside the outermost monofilament roll 2d shown in Figure 1 to create a cylindrical permeable material with a structure of five or more layers. Furthermore, the cylindrical permeable material can also be constructed using only two or three monofilament rolls (or using them and a permeable sheet placed in between).

[0024] (Second embodiment: Method for manufacturing cylindrical water-permeable material) The cylindrical water-permeable material according to the present invention can be manufactured by the following method. First, synthetic resin raw material is supplied to the extrusion molding machine 71 shown in Figure 3, and extrusion molding is performed to push out a linear synthetic resin (monofilament 11) with a diameter of 2 mm (or 1.5 to 2.5 mm) downward from the die 72. A conveyor 81 (belt conveyor or vibrating conveyor) is located below the die 72, and the monofilament 11 extruded from the die 72 is supplied onto the conveyor 81. A pair of parallel side guides 83 (spacing dimension: 50 mm) are arranged at the supply position of the monofilament 11 on the conveyor 81 (on the base end side of the conveyor 81) to define the width dimension (50 mm) of the molded product. The spacing of these side guides 83 can be appropriately changed according to the width dimension of the molded product.

[0025] Figure 4 shows the structure of the lower surface of the die 72 shown in Figure 3. As shown in the figure, the lower surface of the die 72 has several small holes 73 with a diameter of 2 mm that open downwards (a total of four in this embodiment).

[0026] When the monofilament 11 is extruded from the die 72 and supplied onto the conveyor 81, if the transport speed of the conveyor 81 is set to be the same as the extrusion speed of the monofilament 11 from the die 72, the monofilament 11 will be transported on the conveyor 81 in a generally linear shape. However, if the transport speed of the conveyor 81 is set to be slower than the extrusion speed of the monofilament 11, as shown in Figure 5, the monofilament 11 will be transported on the conveyor 81 in a shape that is randomly curved or bent in the longitudinal and lateral directions, and in overlapping parts, curved or bent in the vertical direction.

[0027] As shown in Figure 6, a press belt roller 82 is positioned above the leading edge of the conveyor 81, which can move appropriately in the vertical direction and apply pressing force from above, thereby standardizing the thickness of the molded product passing between the conveyor 81 and the roller (for example, to 15 mm).

[0028] In this way, multiple monofilaments 11 randomly curve or bend and intertwine in three-dimensional directions (longitudinal direction, lateral direction, and vertical direction), creating numerous continuous voids inside, and producing a flat primary molded product 5 with a width of approximately 50 mm and a thickness of approximately 15 mm.

[0029] Furthermore, by adjusting the molding temperature (temperature of the resin immediately after discharge), the resin discharge pressure (discharge speed), the height dimension from the top surface of the conveyor 81 to the bottom surface of the die 72, and the transport speed of the conveyor 81, it is possible to change the curvature or bending of each monofilament 11 on the conveyor 81 (such as the amplitude of the swing in the lateral direction and the average value of the curvature of the curved portion) and the degree of entanglement.

[0030] Furthermore, while Figures 3, 5, and 6 show a belt conveyor as the conveyor 81 for transporting the monofilament 11 or primary molded product 5, a vibrating conveyor that transports the object by vibration can also be used.

[0031] Next, this flat primary molded product 5 is supplied to a roll processing device to be formed into a cylindrical shape. Specifically, four lines (lines A to D consisting of an extrusion molding machine 71 and a conveyor 81, etc., as shown in Figure 6) are prepared for manufacturing the primary molded product 5, and a roll processing device 61 as shown in Figure 7 is prepared. The primary molded product 5A manufactured by line A, the primary molded product 5B manufactured by line B, the primary molded product 5C manufactured by line C, and the primary molded product 5D manufactured by line D are continuously supplied to the roll processing device 61 for molding.

[0032] As shown in Figure 7, the roll processing apparatus 61 consists of a winding shaft 62, a motor 63, side edge guides 64 (first side edge guide 64A to fourth side edge guide 64D) that contact the side edges of the primary molded products 5A to 5D to be supplied and guide the primary molded products 5A to 5D in a spiral direction on the outside of the winding shaft 62, and outer guides 65 (first outer guide 65A to fourth outer guide 65D) that press the primary molded products 5A to 5D to be supplied from the radially outside of the winding shaft 62.

[0033] The winding shaft 62 is connected to the drive shaft of the motor 63 and is configured to rotate in a predetermined direction by the driving force of the motor 63. The side edge guide 64 is made of a C-shaped metal plate that is curved in a spiral shape and is positioned and fixed to surround the outside of the winding shaft 62.

[0034] Furthermore, a gap smaller than the thickness of one layer of the primary molded product 5 (5 mm in this embodiment) is formed between the inner circumference of the first side edge guide 64A and the outer surface of the winding shaft 62; a gap larger than the thickness of one layer of the primary molded product 5 and smaller than the thickness of two layers (20 mm in this embodiment) is formed between the inner circumference of the second side edge guide 64B and the outer surface of the winding shaft 62; a gap larger than the thickness of two layers of the primary molded product 5 and smaller than the thickness of three layers (35 mm in this embodiment) is formed between the inner circumference of the third side edge guide 64C and the outer surface of the winding shaft 62; and a gap larger than the thickness of three layers of the primary molded product 5 and smaller than the thickness of four layers (50 mm in this embodiment) is formed between the inner circumference of the fourth side edge guide 64D and the outer surface of the winding shaft 62.

[0035] The outer guide 65 is made of a metal plate curved into a trough shape and is positioned at a certain distance from the outer surface of the winding shaft 62, surrounding the lower side of the winding shaft 62 (see the first side edge guide 64A and the first outer guide 65A in Figure 8).

[0036] Furthermore, the gap between the first outer guide 65A and the winding shaft 62 is set to the same dimension as the thickness of one layer of the primary molded product 5 (within ±3 mm), the gap between the second outer guide 65B and the winding shaft 62 is set to the same dimension as the thickness of two layers of the primary molded product 5 (within ±3 mm), the gap between the third outer guide 65C and the winding shaft 62 is set to the same dimension as the thickness of three layers of the primary molded product 5 (within ±3 mm), and the gap between the fourth outer guide 65D and the winding shaft 62 is set to the same dimension as the thickness of four layers of the primary molded product 5 (within ±3 mm).

[0037] Primary molded products 5A to 5D are continuously supplied to the roll processing apparatus 61 configured as described above. Specifically, first, the primary molded product 5A manufactured by line A shown in Figure 7 is supplied diagonally to the winding shaft 62 and enters the gap between the winding shaft 62 and the first outer guide 65A. At this time, as shown in Figure 9, the primary molded product 5A is supplied so that its left side edge enters along the first side edge guide 64A. As a result, the primary molded product 5A is guided by the first side edge guide 64A and the first outer guide 65A and wound spirally around the outside of the winding shaft 62, as shown in Figure 10, thereby forming the innermost monofilament roll 2a shown in Figure 1.

[0038] This monofilament roll 2a is sequentially fed toward the tip side of the winding shaft 62 (right side in Figure 10) as the subsequent primary molded product 5A is wound spirally around the winding shaft 62. When the tip portion passes through the area inside the second side edge guide 64B and the second outer guide 65B shown in Figure 7, the gap between the second outer guide 65B and the outer surface of the monofilament roll 2a becomes approximately 15 mm (approximately the same dimension as the thickness of one layer of the primary molded product 5).

[0039] Next, the primary molded product 5B manufactured by line B is supplied diagonally to the winding shaft 62, similar to the primary molded product 5A, and is inserted into the gap between the monofilament roll 2a and the second outer guide 65B. At this time, as shown in Figure 11, the primary molded product 5B is supplied so that its left side edge enters along the second side edge guide 64B. As a result, as shown in Figure 12, the primary molded product 5B is wound spirally around the outside of the monofilament roll 2a, and the second layer of monofilament roll 2b from the inside, as shown in Figure 1, is formed.

[0040] As the subsequent primary molded products 5A and 5B are wound onto this monofilament roll 2b and the monofilament roll 2a inside it, they are sequentially fed toward the tip side of the winding shaft 62 (right side in Figure 12). When the tip passes through the area inside the third side edge guide 64C and the third outer guide 65C shown in Figure 7, the gap between the third outer guide 65C and the outer surface of the monofilament roll 2b becomes approximately 15 mm (approximately the same dimension as the thickness of one layer of the primary molded product 5).

[0041] Then, in a similar manner, the primary molded product 5C manufactured by line C is fed into the gap between the monofilament roll 2b and the third outer guide 65C to form a monofilament roll 2c on the outside of the monofilament roll 2b, and further, the primary molded product 5D manufactured by line D is fed into the gap between the monofilament roll 2c and the fourth outer guide 65D to form a monofilament roll 2d on the outside of the monofilament roll 2c (see Figure 13). In this way, by continuously supplying primary molded products 5A to 5D to the roll processing device 61, a cylindrical water-permeable material consisting of monofilament rolls 2a to 2d can be manufactured.

[0042] Furthermore, a line supplying a water-permeable sheet 3 (nonwoven fabric) is placed between any two of the primary molded product manufacturing lines A to D, for example, between line B which manufactures primary molded product 5B and line C which manufactures primary molded product 5C. As shown in Figure 13, the water-permeable sheet 3 is supplied so that it can be wrapped around the outer surface of the monofilament roll 2b, and the primary molded product 5C is then wrapped around the outside of the water-permeable sheet 3 to form the monofilament roll 2c. This allows for the manufacture of a cylindrical water-permeable material 1 with a cross-section as shown in Figure 1 (i.e., a cylindrical water-permeable material 1 composed of four layers of monofilament rolls 2a to 2d and a water-permeable sheet 3 placed between the monofilament rolls 2b and 2c).

[0043] Furthermore, as shown in Figure 13, by positioning the feed rollers 66 at a location that can contact the outer surfaces of the monofilament rolls 2c and 2d, and supplying driving force to these feed rollers 66 to rotate them in a predetermined direction, the molded product can be smoothly fed towards the tip side of the winding shaft 62 (right side in Figure 13).

[0044] The cylindrical permeable material discharged from the roll processing device 61 is transported to a cooling device (air cooling device, cooling water tank, etc.) for cooling. Then it is cut at the desired length. If monofilaments that are still in an uncured state both internally and externally are brought into contact with each other immediately after extrusion molding and cooled in that state, the contact points will bond to each other. Therefore, the cylindrical permeable material manufactured by the method described above has sufficient rigidity as a whole and can maintain a stable shape because the numerous intertwined monofilaments are bonded together at numerous points and become one.

[0045] Furthermore, it is also possible to perform a step of heating the primary molded product 5 before supplying it to the roll processing device 61, or a step of heating the cylindrical permeable material after discharge from the roll processing device 61. In this case, the contact portions of the entangled monofilaments can be more reliably bonded and integrated by heat welding.

[0046] Furthermore, by using a roll processing device 61 that can wrap one or more primary molded products around the outside of the monofilament roll 2d shown in Figure 13, a cylindrical permeable material consisting of five or more monofilament rolls can be manufactured. In addition, by supplying only primary molded products 5A, 5B (or primary molded products 5A to 5C) to the roll processing device 61, a cylindrical permeable material with a two-layer (or three-layer) structure can also be manufactured.

[0047] In this embodiment, high-density polyethylene powder is used as the main raw material for the monofilament. However, cross-linked high-density polyethylene and an anti-fogging agent (a functional agent for plastic molding) can also be added to this main raw material (in powder form) as auxiliary raw materials. Furthermore, the ratio of the main raw material to the auxiliary raw materials can be 60 to 80 parts by weight (preferably 70 parts by weight) of high-density polyethylene, 20 to 40 parts by weight (preferably 30 parts by weight) of cross-linked high-density polyethylene, and 4 to 10 parts by weight (preferably 7 parts by weight) of the anti-fogging agent.

[0048] Because cross-linked high-density polyethylene has different properties (such as fluidity) from regular high-density polyethylene, when cross-linked high-density polyethylene (secondary material) is mixed with regular high-density polyethylene (main material) in the above-mentioned proportions and extruded, the cross-linked high-density polyethylene in the synthetic resin raw material is extruded from the extruder die in an elongated state. When the extruded synthetic resin (monofilament) comes into contact with air, partial "shrinkage" occurs due to temperature differences. As a result, numerous small irregularities with a height or depth of about 0.1 to 0.5 mm are formed on the surface, resulting in a rough surface rather than a smooth one, and a randomly twisted state. This can be expected to improve the tensile and compressive strength of the molded monofilament.

[0049] Furthermore, when 4 to 10 parts by weight of an antifogging agent, a functional agent for plastic molding, is added as a secondary ingredient, the bleed of surfactants and other components in the additive can impart hydrophilicity to the surface of the monofilaments constituting the water-permeable material, thereby weakening its water-repellent properties. Therefore, when a water-permeable material is manufactured using monofilaments containing an antifogging agent, it can be expected that the material will have better affinity with water and improved drainage performance. [Explanation of Symbols]

[0050] 1: Cylindrical water-permeable material, 2a~2d: Monofilament roll, 3: Permeable sheet, 5,5A~5D: Primary molded product, 11: Monofilament, 61: Roll processing equipment, 62: Winding shaft, 63: Motor, 64: Lateral edge guide, 64A: First lateral edge guide, 64B: Second lateral edge guide, 64C: Third lateral edge guide, 64D: Fourth lateral edge guide, 65: Outer guide, 65A: First outer guide, 65B: Second outer guide, 65C: Third outer guide, 65D: Fourth outer guide, 66: Feed roller, 71: Extrusion molding machine, 72: Dai, 73: Small hole, 81: Conveyor, 82: Press belt roller, 83: Side guide, A-D: Primary molded product manufacturing line

Claims

1. At least two lines are provided for manufacturing a flat, plate-shaped primary molded product having continuous voids inside, by randomly curving or bending multiple monofilaments of synthetic resin, each with a diameter of 1.5 to 2.5 mm, extruded from an extrusion molding machine, in a three-dimensional direction to intertwine them. A roll processing device is prepared that has a winding shaft connected to the drive shaft of a motor and configured to rotate in a predetermined direction by the driving force of the motor. The primary molded product manufactured on a single line is supplied obliquely to the winding shaft and wound spirally around the outside of the winding shaft to form the first layer of monofilament roll. This method is characterized by supplying a primary molded product manufactured on another line at an angle to the winding axis and winding it spirally around the outside of the first monofilament roll to form the second monofilament roll. The roll processing device has a side edge guide that contacts the side edge of the primary molded product being supplied and guides the primary molded product in a spiral direction, and an outer guide that presses the primary molded product being supplied from the radially outside of the winding shaft. The side edge guide has a spirally curved shape, is positioned and fixed to surround the outside of the winding shaft, and is configured to contact the side edge of the supplied primary molded product and guide the primary molded product spirally around the outside of the winding shaft. The outer guide has a trough-shaped curve and is positioned and fixed at a certain distance from the outer surface of the winding shaft, partially surrounding the winding shaft, and is configured to press the supplied primary molded product from the radially outer side of the winding shaft. A method for manufacturing a cylindrical water-permeable material, characterized by supplying a primary molded product so that its side edges follow the side edge guides, and then inserting it into the gap between the outer guide and the winding shaft, or the gap between the outer guide and the inner monofilament roll, and performing the winding.

2. A method for manufacturing a cylindrical water-permeable material according to claim 1, characterized in that a line for supplying a water-permeable sheet is placed between any two of the multiple lines for manufacturing primary molded products, the water-permeable sheet is wrapped around the outer surface of a monofilament roll formed from primary molded products supplied from one line, and then primary molded products supplied from another line are wrapped around the outside of that, thereby placing the water-permeable sheet between two stacked monofilament rolls.

3. A method for manufacturing a cylindrical water-permeable material according to claim 1 or claim 2, characterized in that a feed roller is positioned to contact the outer surface of a monofilament roll, and a driving force is supplied to the feed roller to rotate it in a predetermined direction, thereby feeding the molded product toward the tip of the winding shaft.

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