JP2556359B2 - Method and apparatus for manufacturing synthetic resin porous tube - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention relates to a method for continuously producing a synthetic resin porous tube in which a part of the peripheral surface or the entire peripheral surface is formed in a lattice mesh by extrusion molding. And the device.

(Prior Art and its Problems) As shown in FIG. 5, a synthetic resin porous tube has a lattice-like mesh formed on the peripheral surface along the longitudinal direction or in the entire peripheral surface. The one with a mesh part is
It is suitable as a strainer buried in the ground for drainage pipes of rain gutters, rainwater permeation pipes, etc., and having a mesh on the entire peripheral surface as a strainer attached to the tip of the water absorption pipe of a well.

Conventionally, these synthetic resin perforated pipes are only obtained as a pipe of a predetermined length by injection molding using a mold, and unlike ordinary synthetic resin pipes, they cannot be manufactured as a series of pipes by extrusion molding. It was possible.

(Means for Solving the Problem) On the other hand, the present invention relates to a pipe having a shape in which a large number of ridges are arranged side by side along the longitudinal direction on the inner peripheral surface, and a cut line that crosses the pipe leaving the ridges on the peripheral surface. It was developed by paying attention to the fact that when the pipes are lined up and the pipe is pulled, the ridges at the part between these cuts are stretched and formed into a grid-like mesh, which is mounted on a normal extrusion molding machine. In this way, a synthetic resin porous tube can be easily manufactured.

(Embodiment of the Invention) Referring to the drawings, an embodiment of the apparatus according to the present invention will be described. FIG.
Is an extrusion die, 3 is cooling water, and 4 is a tension roller. These are structurally similar to a normal extrusion molding apparatus, but in the present invention, the product a extruded from the extrusion die 2 is a. Is a tube portion b as is apparent from FIG.
Is a tube body in which ridges c ... Are formed along a longitudinal direction on a part of the inner surface of the tension roller 4, and the tension roller 4 forcibly pulls the product a at a slightly higher speed due to the extrusion speed of the extruder 1. Is made to do.

Next, 5 is a notch forming mechanism which constitutes a main part of the present invention, and is connected and attached to the tip of the extrusion die 2 to make incisions at regular intervals on the peripheral surface of the product a fed from the extrusion die. It is for attachment. As shown in FIGS. 2, 3, and 4, this cut forming mechanism has a sprocket wheel 8 on the outer surface of a cylindrical body portion 7 having a circular hole 6 through which the product a can pass. A cam that is rotatably fitted separately from 7 and is provided with a cutter 9 slidably on the plate surface of the sprocket wheel 8 along a radial position, and the cutter 9 is separately fitted and fixed to the tubular portion 7. It slides in accordance with the rotation of the sprocket wheel through 10, and cuts the outer peripheral surface of the product a at its tip. That is, the sprocket wheel 8 is rotatable by engaging the roller 11 axially supported on its plate surface with the guide flange portions 12, 13, 14 of the cylindrical body portion 7, and the cutter 9 is rotatable with respect to the sprocket wheel 8. A sliding member 17 whose one end is pressed against the peripheral surface of the cam 10 via a roller 16 by a spring 15 is attached to the plate surface, and the tip is always pressed against one end of the cylindrical portion 7 via a spring 18. ing. Reference numeral 19 is a nut-shaped tightening ring for fixing the cam 10, and 20 is a screw mounting hole for fixing the tubular portion 7 to the extrusion die 2.

With this configuration, the pellet-shaped thermoplastic resin which is the raw material is supplied to the extruder 1, and the product a having a shape in which the ridges c ... Are juxtaposed in the upper half of the inner peripheral surface through the extrusion die 2. And pulling it out by forcibly pulling it out with the tension roller 4, and the sprocket wheel 8 of the notch forming mechanism 5 connected and attached to the tip of the extrusion die 2 through the chain 21 at 200 to 500 rpm. Then, the cutter 9 attached to the sprocket wheel 8 via the sliding member 17
Is swiveled around the product a while sliding through a cam 10 having a slightly larger circumference according to the sectional shape of the product a in advance, and the tip of the cutter passes through the upper half of the product a. When the product a passes through the lower half part of the product a, when the product a passes through the lower half part of the product a, the part having the ridges c ... Is cut while leaving the ridges c. As a result of being constantly pulled by the ridges, the ridges c ... Between the cuts are uniformly stretched to continuously produce a synthetic resin porous tube as shown in FIG.

In this case, if the product a is a tubular body having a ridge on its inner peripheral surface and the cam is a perfect circle along the pipe portion b of the product a, It is possible to make a synthetic resin porous tube whose surface is made porous.

(Effects of the Invention) As described above, the present invention creates a synthetic resin porous tube, which has been conventionally molded as a tube of a fixed length, as a continuous series of tubes by extrusion molding like an ordinary synthetic resin tube. In addition, as described above, it is extremely efficient because it is possible to make a synthetic resin perforated pipe of a different type simply by replacing the extrusion die 2 of the extruder and the cam 10 of the cut forming mechanism, respectively. In addition, there are many advantages such as low production cost.

[Brief description of drawings]

1 to 4 show an apparatus according to the present invention.
The figure is a side view of the whole, FIG. 2 is a side view of the notch forming mechanism, and FIG.
FIG. 4 is a rear view of the same, FIG. 4 is an exploded perspective view of the same, and FIG. 5 is a perspective view showing an example of a synthetic resin porous tube made according to the present invention. 1 ... Extruder, 2 ... Extrusion die, 4 ... Tension roller, 5 ... Notch forming mechanism, 7 ... Cylindrical part, 8 ...
Sprout wheel, 9 ... Cutter, 10 ... Cam, 1
1,16 …… Roller, 17 …… Sliding member, 15,18 …… Spring,
a: product, b: tube, c: ridge.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Office reference number FI technical display location B29L 31:14

Claims (2)

(57) [Claims] 1. A product in which ridges are arranged in a row along the longitudinal direction on the inner peripheral surface of a pipe is continuously produced by extrusion molding, and the ridges are left in the product, and cuts across the pipe are spaced at regular intervals. The method for producing a synthetic resin perforated pipe, wherein the product is towed in the extrusion direction and the ridges extending between the cuts are stretched to form a grid-like mesh. 2. An extruder for continuously producing a product in which ridges are lined up along the longitudinal direction on the peripheral surface of a tubular body, and a short tubular cut formation connected to an extrusion die of the extruder. Mechanism,
The notch forming mechanism comprises a cutter that rotates along the outer peripheral surface of the tubular body surrounding the product, and the cutter is a cam that is previously fitted and attached to the tubular body. A device for manufacturing a synthetic resin porous tube in which the tip of the cutting edge is always held toward the center of the cylindrical body to cut the product to a depth where the ridge is left.