JP2903490B2 - Method for producing spherical three-dimensional net-like aggregate - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a three-dimensional reticulated aggregate, particularly a spherical three-dimensional reticulated aggregate, used as a filter material for sewage treatment and the like which fills a sewage treatment tank and causes microorganisms contributing to sewage treatment to adhere and multiply. And a method for producing the same.

[0002]

2. Description of the Related Art Conventionally, synthetic resin filaments formed into a three-dimensional net-like shape and formed into a mat shape, a rod shape, a pipe shape, etc. are disclosed, for example, in Japanese Patent Publication No. 62-60494 and Japanese Patent Publication No.
It is publicly known, for example, from US Pat. However,
Since the shape of these three-dimensional net-like aggregates has directionality, for example, only insufficient performance was exhibited for a three-dimensional flow of sewage. Therefore, the appearance of a spherical three-dimensional net-like aggregate, which has a uniform net-like structure in any direction and is expected to improve performance, is strongly desired, but its production has been extremely difficult.

[0003]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a method for easily obtaining a spherical three-dimensional net-like aggregate in order to meet the above demand.

[0004]

In order to achieve the above object, a method for producing a spherical three-dimensional net-like aggregate according to the present invention comprises the steps of: forming a molten synthetic resin material having an appropriate viscosity into a nozzle 2 of an extruder 1; A plurality of continuous filaments 3 are formed by extruding downward from the nozzle 2, and a rotatable, substantially spherical rotor 6 having a smooth surface is disposed at a position below the nozzle 2, and is disposed at an outer peripheral position of the rotor 6. An arc-shaped mold 7 which is bent in an arc shape and has a concave portion 9 having a substantially semicircular cross section on its inner surface is arranged, and the lower surface of the rotor 6 which rotates the filament 3 hanging from the nozzle 2 is slower than its descending speed. The three-dimensional net-like continuous aggregate 13 is passed between the rotor 6 and the arc-shaped mold 7 while being adhered to each other and assembled into a three-dimensional net by utilizing the adhesiveness in a molten state that has not been solidified yet by being twisted by being received. The and its cross-section bent in an arc shape without a hollow generally semi-circular cooled and solidified following the their shape by, thereafter, the stereoisomers reticular continuous assembly 1
3 is a belt conveyor 10 having a projection 11 on a belt 11
After that, the three-dimensional net-like continuous aggregate 13 is cut into a required length, and its both end cut surfaces are joined together and integrally joined.

[0005]

An embodiment will be described below with reference to the drawings. FIG. 1 is a schematic sectional view of an apparatus used to carry out the present invention. A number of nozzles 2 are provided on the lower surface of the extruder 1, and a thermoplastic synthetic resin such as polypropylene is heated and melted and extruded from the nozzles 2. This molten resin has a suitable viscosity and forms a continuous filament 3. Below the nozzle 2, a water tank 5 filled with cooling water 4 is arranged.
The rotor 6 is located inside the nozzle 2 below the nozzle 2.
And an arc-shaped mold 7 are arranged. The rotor 6 has a substantially spherical shape with a smooth surface, and is rotatable in one direction by a rotating shaft 8. The arc-shaped mold 7 is bent in an arc shape in the rotation direction of the rotor 6 and has a shape having a concave portion 9 having a substantially semicircular cross section on the inner surface. It is arranged with a gap. The upper half of the rotor 6 and one end of the circular mold 7 are exposed above the water surface, and the other end of the circular mold 7 is submerged in water. A pair of belt conveyors 10 are opposed to each other in parallel with a certain gap on a substantially extended line obliquely above one end of the arc-shaped mold 7 submerged in water. The belt 11 of the belt conveyor 10 is provided with protrusions 12 at regular intervals.

[0006] The filament 3 pushed out from the nozzle 2 and continuously hung is received by the upper surface of the rotor 6 in a state where it has not yet solidified and has a suitable tackiness, and is rotated by the rotation of the rotor 6. And into the gap between the circular mold 7. At this time, the striatum 3 is
, Ie, the rotation speed of the rotor 6 is made slower than the descending speed of the filaments 3, the filaments 3 meander in a wrinkle-like manner and gather together in a three-dimensional network while sticking to each other due to their adhesiveness. The three-dimensional net-like continuous aggregate 13 passes between the rotor 6 and the arc-shaped mold 7, so that the three-dimensional net-like continuous aggregate 13 is bent in an arc shape in the traveling direction and has a hollow cross section. Is formed into a substantially semicircular shape. Then, it is cooled by the cooling water 4 and solidified as it is. Thereafter, the three-dimensional net-like continuous aggregate 13 is stretched linearly, passes between the pair of belt conveyors 10, is hooked on the protrusions 12 provided on the belt 11, and is taken by the movement of the belt 11. The moving speed of the belt 11, that is, the take-up speed of the three-dimensional net-like continuous aggregate 13 and the rotational speed of the rotor 6 are set to be the same. After that, when the three-dimensional net-like continuous aggregate 13 is cut to a required length, it is restored to the shape formed by the rotor 6 and the arc-shaped mold 7 due to elasticity, as shown in FIG. Since it is rounded, the cut surfaces at both ends thereof are aligned with each other, and are integrally joined by an appropriate means such as heat welding or using a connection fitting. Thus, a hollow spherical three-dimensional net-like aggregate 14 as shown in FIG.

[0007]

As described above, according to the present invention, a substantially spherical rotor 6 which is rotatable and has a smooth surface, and an arc-shaped mold 7 which is bent in an arc shape and has a recess 9 having a substantially semicircular cross section on the inner surface. After being cooled and solidified through the three-dimensional net-like continuous aggregate 13, the three-dimensional net-like continuous aggregate 13 is taken out by the belt conveyor 10, cut into a required length, and both end cut surfaces are integrally joined. This has an effect that the spherical three-dimensional net-like aggregate 14 can be easily obtained. Further, the present invention provides a three-dimensional net-like continuous aggregate 13 in an unsolidified state by using a rotor 6 having a smooth surface and an arc-shaped mold 7.
Is formed into a round shape.
The product can be obtained with stable quality without adverse effects such as the shape of the belt being caught by protrusions and irregularities, and the solid reticulated continuous aggregate 13 is taken out by the belt conveyor 10 after being cooled and solidified. 12 has an advantage that the wire 3 can be smoothly picked up without any adverse effect such as sticking of the filament 3.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view of a manufacturing apparatus.

FIG. 2 is an end view taken along the line AA of FIG. 1;

FIG. 3 is a plan view showing a process of cutting a continuous three-dimensional net-like aggregate into a required length, and then joining the cut surfaces at both ends to complete a spherical three-dimensional net-like aggregate.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Extruder 2 Nozzle 3 Wire 4 Cooling water 5 Water tank 6 Rotor 7 Arc-shaped mold 8 Rotating shaft 9 Concave part 10 Belt conveyor 11 Belt 12 Projection 13 Solid continuous net aggregate 14 Spherical solid net aggregate

Claims (1)

(57) [Claims] 1. A synthetic resin material in a molten state having a suitable viscosity is extruded downward from a nozzle 2 of an extruder 1 to form a plurality of continuous filaments 3 and rotated to a position below the nozzle 2 A generally spherical rotor 6 having a free and smooth surface is arranged, and an arc-shaped mold 7 which is bent in an arc shape at an outer peripheral position of the rotor 6 and has a concave portion 9 having a substantially semicircular cross section on its inner surface is arranged. By receiving the filaments 3 hanging down from the nozzle 2 on the outer surface of the rotating rotor 6 at a speed lower than the descending speed, the filaments 3 are twisted and gathered together in a three-dimensional net shape by utilizing the tackiness in a molten state which has not solidified yet. At the same time, by passing the three-dimensional net-like continuous assembly 13 between the rotor 6 and the arc-shaped mold 7, it is bent into an arc shape in accordance with the shape thereof, and the cross-section thereof is formed into a substantially semicircular hollow shape to cool and solidify. Then, after that, the three-dimensional net-like continuous aggregate 13 is pulled out by the belt conveyor 10 provided with the protrusions 12 on the belt 11, and then the three-dimensional net-like continuous aggregate 1 is taken out.
3. A method for producing a spherical three-dimensional net-like aggregate, comprising cutting a piece 3 into a required length, joining cut surfaces at both ends thereof, and integrally joining them.