JP4130281B2 - Manufacturing method of reticulated plastic molding - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention is used as a member for supporting a filter medium in a septic tank, or as a member constituting a fence or a decorative wall surface, and is expected to be used in various other industrial fields. The present invention relates to a method for manufacturing a body.
[0002]
[Prior art]
A septic tank that purifies sewage by biological treatment is filled with a large number of filter media. As a member for supporting these filter media in the tank, for example, as shown in FIG. 12, a plate member 121 made of plastic and a pipe 122 are assembled in a lattice pattern with a gap of a size that prevents the filter media from falling off. Things were used. The size of the support member varies depending on the capacity of the septic tank to be used, but when a spherical filter medium having a diameter of about 90 mm is filled, the length and width are each about 1 m.
[0003]
[Problems to be solved by the invention]
The conventional support member requires time and labor for assembling the plate member 121 and the pipe 122 in a lattice shape, and the number of processing steps has to be increased. As a method of manufacturing the support member, for example, a method of integrally molding by injection molding or connecting several grid blocks formed separately to form an integral support member is not conceivable. However, in the former, it is impossible to integrally form a frame having a size exceeding 1 m in length and breadth due to cost constraints, and in the latter, the rigidity of the connecting portion between the blocks is lowered, and the entire support member is sufficiently supported. There is a problem that strength cannot be obtained. For this reason, as described above, there is no means for obtaining a single support member having high rigidity without taking time and in addition to manufacturing manually using the plate material 121 and the pipe 122, and the cost for manufacturing the support member cannot be reduced. It was.
[0004]
This invention makes it a subject to enable it to manufacture efficiently the net-like plastic molded object as a supporting member which supports a filter medium within a septic tank in view of such a problem which a prior art has.
In addition, the reticulated plastic molding obtained by the manufacturing method of this invention can be utilized also as a support member of a fence, a decorative wall surface, a flower pot, etc. besides being used as a support member of a filter medium.
[0005]
[Means for Solving the Problems]
In order to solve the above-described problems, the method for producing a reticulated plastic molded body of the present invention includes forming a plate-like molded body in which concave grooves are arranged at a predetermined interval by extrusion molding, and forming a certain amount in each concave groove of the plate-like molded body. Periodic incisions in the extrusion direction are formed so as to be the same period every other row by shifting the formation period by half a period between adjacent grooves, and each incision is in a direction perpendicular to the extrusion direction. A plurality of the same-shaped gaps are provided in the plate-shaped molded body by widening with a predetermined width.
[0006]
According to this method, a step of extruding a plate-shaped molded body, a step of forming cuts in the plate-shaped molded body at a predetermined interval, and a step of widening the cuts are performed. In addition, it can be efficiently produced in-line with a series of production processes of plastic molded products, and the conventional labor-intensive work is unnecessary, and the production cost can be reduced.
[0007]
In the above method, the thickness of the plate-shaped molded product, the height and width of the concave groove, the length of the cut formed in the concave groove, the ratio with the portion without the cut, or the dimension for widening the cut, etc. The shape and size of the gap to be formed changes, but in order to maintain rigidity, the incision is formed with a dimension in which the ratio of the incision length and the length between the incisions is approximately 3: 1. It is preferable that the widened gap has a substantially regular hexagonal shape.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
Preferred embodiments of the present invention will be described with reference to the drawings.
The method for manufacturing a reticulated plastic molded body of this embodiment includes a step of extruding a plate-shaped molded body, a step of blowing air to form, a step of forming cuts at a predetermined interval in the plate-shaped molded body, and blowing air. The first step for widening the cut, and the second step for widening the cut. Hereinafter, each process is demonstrated in order.
[0009]
First, in the extrusion molding process, a plastic plate such as a hard vinyl chloride resin is used as a raw material, and a die having a tip shape with ribs protruding at a predetermined interval in a vertical direction is attached to the extruder, and an appropriate thickness plate The shaped molded body 1 is extruded.
As shown in FIG. 1, the extrusion-molded plate-like molded body 1 has concave grooves 11 extending continuously along the extrusion direction on both the upper and lower surfaces so as to face each other on the upper and lower surfaces and in the width direction. The cross-sectional shape is arranged at intervals.
[0010]
Next, in the air blowing step, air is blown onto the surface of the plate-like molded body 1 to mold it. The air is blown while the plate-like molded body 1 is passed through a mold having the same shape as the mold having ribs corresponding to the concave grooves 11. By blowing air, the plate-like molded body 1 has a good surface slip and is solidified by cooling.
[0011]
Next, in the notch forming process, as shown in FIGS. 2 and 3, a circular shape is formed in the flow path of the plate-like molded body 1 that has been pushed out of the mold 2 and passed through an air blowing mold (not shown). The punching machine 3 having the slit blade 31 is installed, and the notch 12 is formed in each concave groove 11 while the plate-like molded body 1 is allowed to flow into the punching machine 3.
The punching machine 3 is configured by a rotatable liner 32 having slit blades 31 so as to enter the respective concave grooves 11 from above, and a rotatable receiving roll 33 for guiding the lower side of the plate-like molded body 1. Yes. As shown in FIG. 2, each slit blade 31 is formed in a shape in which cut portions 31a and non-cut portions 31b are arranged symmetrically with a phase difference of 180 ° on the periphery thereof. It arrange | positions so that a phase may shift | deviate 90 degrees with the blade 31, and is attached to the rotating shaft of the liner 32 arrange | positioned in the direction orthogonal to a flow direction above the flow path of the plate-shaped molded object 1. FIG.
As shown in FIG. 3, the receiving roll 33 is formed in a cylindrical shape in which concave portions 33 a and convex portions 33 b corresponding to the unevenness of the plate-like molded body 1 are arranged on the peripheral surface. The rotating shaft is installed in the direction perpendicular to the flow direction below the flow path. Further, the receiving roll 33 has its concavo-convex portions 33 a and 33 b of the plate-shaped molded body 1 so that a gap of play is maintained between the receiving roll 33 and the surface of the plate-shaped molded body 1 when guiding the plate-shaped molded body 1. Each of the convex portions 33b is provided with a groove 33c for guiding the slit blade 31 that penetrates the concave groove 11 and is formed to be slightly smaller than the width of the unevenness on the surface.
Both the liner 32 and the receiving roll 33 rotate so that the peripheral edge is rotated in the same direction and at the same speed as the flow of the plate-shaped molded body 1, and the plate-shaped molded body 1 sequentially pushed out from the mold 2 is a punching machine. While passing through 3, the slit blade 31 is inserted into the concave grooves 11 from above while being guided by the receiving roll 33 on the lower side thereof, and the cuts 12 are continuously formed at regular intervals.
As shown in FIG. 4, the plate-like molded body 1 by passing through the punching machine 3 has a period (T) that is half the length of the outer periphery of the slit blade 31, that is, the cut portion 31 a and the non-cut portion. Incisions 12 are formed in the respective concave grooves 11 with a period of a length of 31b. Further, as described above, the adjacent slit blades 31 are arranged so that the phases are shifted by 90 °, so that the formation period of the cuts 12 is shifted by a half period between the adjacent concave grooves 11 and the same period every other row. Formed as follows.
[0012]
The plate-like molded body 1 in which the cuts 12 are formed is cooled by air blown on the surface so that the cuts 12 do not expand in the air blowing process similar to the above, which is provided immediately after the cut forming process. Solidified.
[0013]
Next, in the first step of widening the cuts, the cuts 12 are widened by gradually increasing the widths of the concave grooves 11 while the plate-like molded body 1 is conveyed on the flow path.
As shown in FIG. 5, the widening is a width (1.1 × w, 1.2 × w) slightly larger than the width of the unevenness (w, see FIG. 1) on the surface of the plate-like molded body 1. A plurality of rolls 4 having concavo-convex portions 41 on the peripheral surface are arranged in the flow path so as to be able to contact the plate-shaped molded body 1, and the width of the concavo-convex portions 41 of each roll is the width of the concavo-convex on the surface of the plate-shaped molded body 1. In contrast, 1.1 times, 1.2 times, 1.3 times, 1.4 times, 1.5 times, and so on by gradually increasing the size of each roll 4 As the plate-shaped molded body 1 passes, the groove 11 is gradually expanded in the width direction perpendicular to the extrusion direction at the concavo-convex portion 41.
As shown in FIG. 6, the plate-like molded body 1 that has passed through each roll 4 has an overall width that increases along with the widening of the concave grooves 11, and the notch 12 of each concave groove 11 is predetermined in the length direction by the widening. It becomes a long hole-like slit which continued at intervals.
[0014]
Next, in the second step of widening the cut, the long hole-shaped cut 12 is further widened in the width direction.
The widening in this step is performed by, for example, cutting the plate-shaped molded body 1 widened in the first step into an appropriate length, passing it through a heating furnace and softening it, and then moving forward and backward in the width direction on both sides thereof. This can be done by attaching each cylinder to be driven and driving the cylinder in the direction in which the notch 12 widens. In this case, it is preferable that a guide member is applied so that the plate-shaped molded body 1 is sandwiched from both the upper and lower surfaces so that the in-plane does not bend as the plate-shaped molded body 1 extends in the width direction.
In the plate-like molded body 1 in which the notches 12 are further widened in the second step, as shown in FIG. 7, each notch 12 has a hexagonal gap in the shape of a turtle having the same shape and the same size. 13a is formed into a frame-shaped net-like molded body 13 having a large number of gaps 13a on the surface as a whole.
[0015]
As shown in FIG. 8, the net-like molded body 13 formed through the above steps is cut into appropriate dimensions, attached with a frame plate 5 around it, and used as a support member that supports the filter medium in the septic tank. Can be used. The illustrated supporting member has a size of 870 mm in length (width) and 1090 mm in width (length), and is formed so as to be able to support a spherical filter medium having a diameter of about 90 mm.
[0016]
In the above-described process, the slit 12 is formed using the rotating slit blade 31, but may be formed by other means such as using a slit blade that moves up and down. Moreover, although the process of widening the notch 12 is divided into the first and the second, it is possible to widen within one process by using only the roll 4 or only the cylinder or using other widening means. Good.
Moreover, the thickness of the plate-shaped molded body 1 extruded in the extrusion molding process, the height (t), the width (w), and the formation interval (d) of the groove 11 can be set to appropriate dimensions (FIG. 1). FIG. 9 shows an example, and FIG. 9A shows a case where the width and interval of the concave grooves 11 are set to be approximately the same size, and FIG. 9B shows that the width of the concave groove 11 is larger than the interval in order to increase the strength. When the size is set, FIG. 3C shows the case where the thickness of the plate-like molded body 1 is reduced and the height and width of the concave groove 11 are also set small. Further, in order to enhance the decorative effect of the net-like molded body 13, the corners of the surface of the plate-like molded body 1 may be formed in a curved surface as shown in FIG. ), The groove 11 may be provided only on one of the upper and lower surfaces of the plate-like molded body 1.
Further, as shown in FIGS. 10A to 10C, the length of the notch 12 to be formed in the concave groove 11, the ratio of the notched portion, the dimension for widening the notch, and the like are appropriately set. Thus, the shape and size of the gap 13 can be freely adjusted, but the ratio of the length (L1) of the notch 12 to the length (L2) between the notches (see FIG. 4) is approximately 3: 1. If the gap 13 is widened and set so that it has a substantially regular hexagonal shape, even when stress is applied to the net-like molded body 13 from the front, rear, left and right, this is evenly distributed to increase the rigidity. Can be kept high. L1 corresponds to the length of the cut portion 31a of the slit blade 31, and L2 corresponds to the length of the non-cut portion 31b.
[0017]
As described above, according to the method of the present invention, the plastic material in the step of extruding the net-like molded body 13 from the plate-like molded body 1, the step of forming the cuts 12 in the plate-like molded body 1, and the step of widening the cuts 12 is obtained. It can be efficiently produced in-line in a series of production processes of the molded product, and the production cost can be reduced compared with the case of producing the same shape product by a conventional method.
In addition, the net-like molded body 13 manufactured by the method of the present invention is used as a member for supporting a flower pot, as shown in FIG. (A)), it is colored and used as a fence in a garden or a park (FIG. (B)), or it is expected to be used in various industrial fields such as building members that make up wall surfaces.
[0018]
【The invention's effect】
ADVANTAGE OF THE INVENTION According to this invention, the net-like plastic molding used as a supporting member which supports a filter medium within a septic tank, or used in another industrial field can be manufactured efficiently.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view of an essential part of a plate-like molded body formed in an extrusion process of a method of the present invention.
FIG. 2 is a view showing a state in which a slit blade is placed in a concave groove of a plate-like molded body.
FIG. 3 is a cross-sectional view showing a configuration of a punching machine.
FIG. 4 is a diagram for explaining a ratio and a position of a length of a cut formed in a concave groove of a plate-shaped molded body.
FIG. 5 is a diagram for explaining a step of widening the cut using a roll.
FIG. 6 is an external view of a plate-like molded body in which a cut is widened using a roll.
7 is an enlarged external view of a main part of a net-like molded body formed by further widening the cut from the state shown in FIG.
FIG. 8 is an external view of a filter medium support member formed using a net-like molded body.
FIGS. 9A to 9E are views showing a cross section of a main part of a molded plate-like molded body in which a dimensional ratio or the like is changed.
FIGS. 10A to 10C are diagrams showing modified examples of the shape of the widened gap by forming notches by changing the dimensional ratio and the like. FIGS.
FIGS. 11A and 11B show other uses of the net-like molded body, in which FIG. 11A is an external view used as a potting support member, and FIG. 11B is an external view used as a fence.
FIG. 12 is an external view of a conventional filter medium support member.
[Explanation of symbols]
1 Plate shaped body
11 groove
12 notches
13 Reticulated body
2 Mold
3 Drilling machine
31 Slit blade
33 Receiving roll
4 rolls

Claims (2)

A plate-like molded body in which concave grooves are arranged at predetermined intervals is formed by extrusion molding, and a predetermined length of cut is periodically formed in each concave groove of the plate-shaped molded body in the extrusion direction, and adjacent concave grooves A plurality of gaps of the same shape are formed in the plate-shaped molded body by expanding the incisions by a predetermined width in the direction perpendicular to the extrusion direction by shifting the formation period by half a period between them to form the same period every other row. A method for producing a reticulated plastic molding, comprising: The reticulated plastic molded body according to claim 1, wherein the cut is formed with a dimension in which the ratio of the length of the cut and the length between the cuts is approximately 3: 1, and the widened gap is a substantially regular hexagon. Method.

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