JPH058092B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a synthetic resin pipe, and more particularly to an apparatus for manufacturing a synthetic resin pipe whose outer wall is provided with a spiral protrusion and whose inner wall is a flat surface.

(Prior art) In general, this type of synthetic resin pipe has an outer spiral protrusion made of hard synthetic resin, and an inner flat inner wall made of soft synthetic resin. Publication No. 53179 and Japanese Unexamined Patent Publication No. 57-110426
As disclosed in the above publication, a first molding die supplies a strip material having a U-shaped cross section to become a protrusion to the molding main shaft, and a second molding die supplies a strip material having a flat inside to a flat plate shape. The two strip materials were then fused together on the main shaft for forming.

(Problems to be Solved by the Invention) However, as described above, a synthetic resin pipe having a spiral protrusion made of hard synthetic resin on the outside and a flat inner wall made of hard synthetic resin on the inside is manufactured by Since two molding molds are required, the structure of the entire device becomes very complicated, and this results in a problem in that the manufacturing process is time-consuming and increases the manufacturing cost.

(Means for Solving the Problems) The present invention was invented to solve the problems as described above, and includes a molding die for supplying a synthetic resin strip material to a molding main shaft. A first passageway for molding a U-shaped part with narrow plate-like parts on both side edges using a semi-molten hard synthetic resin, and a second passage for molding a wide plate-like part from a semi-molten hard synthetic resin. is formed, and the molding passage portion of the narrow plate-shaped portion on one side in the first passage and the molding passage portion of the edge portion on one side of the wide plate-shaped portion in the second passage are communicated with each other in front of the exit to form a common passage portion. It has a cross-sectional shape including a U-shaped portion, a narrow plate-shaped portion extending from one side of the opening edge of the U-shaped portion, and a wide plate-shaped portion extending from the other side of the opening edge, and the U-shaped portion and the narrow plate-shaped portion extend from the other side of the opening edge. The present invention is characterized in that the plate-shaped portion is made of a hard synthetic resin, and the large plate-shaped portion is configured to mold and supply a strip material made of a soft synthetic resin.

(Function) The semi-molten synthetic resin strip material extruded from the molding die and supplied to the molding spindle is wound up in a spiral as the spindle rotates. When winding a strip material, the U-shaped part of the following strip material is wound on the wide plate-shaped part of the strip material that was wound before the main shaft, and the following strip material is wrapped around the wide plate-shaped part of the preceding strip material. The narrow plate-shaped part of the U-shaped part and the part near the U-shaped part of the wide plate-shaped part are welded,
A so-called tube body is continuously formed. In addition, in the tube formed in this way, the U-shaped part is made of hard synthetic resin and the large plate-shaped part is made of soft synthetic resin, so the outer spiral protrusion is made of hard synthetic resin. This increases its flat strength, and the flat inner wall is made of soft synthetic resin to ensure its flexibility.Furthermore, since the inner wall is flat, it can be used, for example, when passing electric wires inside a pipe. , the insertion work can be easily carried out, or when used as a drain pipe, the flow resistance can be made extremely small.

(Example) An example of the present invention will be described in detail below based on the drawings.

In the figure, 11 is a cylindrical main shaft for molding, and the main shaft 11 is extrapolated onto the fixed shaft 13, and
Bearings 14 are interposed between the inner periphery of both ends of the main shaft 11 and the outer periphery of the fixed shaft 13.
1 is rotatably supported on a fixed shaft 13, and one end of the fixed shaft 13 is supported on a base 12 in a cantilevered manner. Further, the main shaft 11 is interlocked with a drive device (not shown) via a transmission mechanism such as a pulley 15, and a plurality of rod-shaped or disc-shaped magnet groups 16 are embedded in the main shaft 11, and a rotor 18 (described later) is configured to be attracted onto the main shaft 11. The main shaft 11 can also be supported directly on the base 12 in a cantilevered manner without using the fixed shaft 13.

Further, a large number of rotors 18 are arranged around the outer circumference of the main shaft 11.
They are arranged in a plurality of rows in the length direction of the main shaft 11, and the row direction of the row-shaped rotors 18 is the main shaft 1.
1, and a core shaft 17 extending from the base 12 is inserted through the row-shaped rotor 18 group, so that the row-shaped rotor 18 group is rotatably supported on the main shaft 11. At this time, the free end of the core shaft 17 is engaged with an end plate 20 which is fixed by tightening a nut 19 to the free end of the fixed shaft 13. The rotor 18 is made of iron-based metal, and a group of magnets 16 are arranged around the outer periphery of the main shaft 11.
It is designed to be absorbed by

Further, between each row of the row-shaped rotor group 18, there is a rotor 1
A rod-shaped member 21 having a diameter smaller than 8 and having a length extending from the base end to the distal end of the row-shaped rotor 18 group is interposed, and one end of this rod-shaped member 21 is connected to the base 12.
At the same time, the other end is fitted into a U-shaped recess 22 formed in the end plate 20, and this rod-shaped member 21 is brought into contact with the adjacent group of row-shaped rotors 18, and each of the row-shaped rotors is It is configured to regulate the spacing between rows. The rod-shaped member 21 is made of a synthetic resin with a small coefficient of friction, such as nylon or Teflon.

On the other hand, a strip material 1 of a predetermined shape made of semi-molten synthetic resin is attached to 18 groups of row-shaped rotors on the main shaft 11 for molding.
A molding die 23 for supplying a is provided. As shown in FIGS. 6 to 8, this mold 23 includes a first passage 23a for molding a semi-molten hard synthetic resin, and a second passage 23b for molding a semi-molten soft synthetic resin. The first passage 23a has a narrow plate-like portion 2a-1,
2a-2 is formed, and the second passage 2 is formed.
3b is for forming the wide plate-like portion 3a, and both passages 23a and 23b are partially overlapped in front of the exit, that is, the forming passage portion of the narrow plate-like portion 2a-2 in the first passage 23a and the second passage The wide plate portion 23b is configured to communicate with the molded passage portion at one side edge of the U-shaped portion 3a to form a common passage, and the U-shaped portion 2a and the narrow plate portion extending from one side of the opening edge of the U-shaped portion 2a. 2a-
1, and a large plate-shaped portion 3a extending from the other side of the opening edge.
A strip material 1 exhibiting a cross-sectional shape having the following, in which the U-shaped portion 2a and the narrow plate-shaped portion 2a-1 are made of hard synthetic resin, and the wide plate-shaped portion 3a is made of soft synthetic resin.
A is configured to be molded and supplied. Also, molding mold 2
A pair of molding maintenance rollers 24 and 25 are provided between the molding main shaft 11 and the molding main shaft 11.
The purpose is to prevent deformation of each material 1a to be supplied.
A plurality of sets of the forming maintaining rollers 24 and 25 may be provided.

In addition, in FIGS. 8 and 10, the joint between the narrow plate-like portion 2a-2 and the wide-width plate-like portion 3a is demarcated by a clear division line for convenience, but in reality, the two merge and are clearly demarcated. It is not something that will be done.

The apparatus of the present invention is constructed as described above, and when the molding main shaft 11 is driven and rotated, the row-shaped rotors 18 group supported by the core shaft 17 and attracted onto the main shaft 11 by the magnet group 16 move onto the main shaft 11. At this time, the row rotor 18
Since the row direction of the group is inclined with respect to the axis of the main shaft 11, the strip material 1a supplied onto the rotor 18 from the molding die 23 is wound up in a spiral shape. At the time of winding, the inclination angle of the group of row rotors 18 with respect to the main shaft 11 is set so that the helical feed pitch of the strip material 1a is smaller than the width dimension of the strip material 1a. Both side edges of 1a are sequentially overlapped by a constant width and welded to each other, so that the tube body 1 is continuously formed.

Further, during the above-described molding, each row-shaped rotor 18 group is pulled to one side (the front side in the rotational direction of the main shaft 11) as the strip material 1a is wound up. Since the rod-shaped members 21 are interposed between the rows, the spacing between each row is reliably maintained, and thereby the inclination angle of each group of row-shaped rotors 18 is reliably maintained. .

On the other hand, as described above, the strip material 1a is extruded from the molding die 23 and supplied to the molding spindle 11.
is wound up spirally as the main shaft 11 rotates, the strip material 1 previously wound around the main shaft 11
The U-shaped part 2'a of the following strip material 1'a is placed on the wide plate-shaped part 3'a extending from the narrow plate-shaped part 2a-2 of a.
is wound around the wide plate-like portion 3''a extending from the narrow plate-like portion 2'a-2 of the strip material 1'a, and the subsequent U-shaped portion 2''a of the strip material 1''a is wound. Between these U-shaped parts 2a and 2'a,
The wide plate part 3a and the narrow plate part 2'a-1 are overlapped from both sides at the joint between the narrow plate part 2a-2 and the wide plate part 3'a, and the U-shaped part 2'a ,2″
From both sides of the joint between the narrow plate-like part 2'a-2 and the wide-width plate-like part 3''a between the wide plate-like parts 3'a
and the narrow plate-like portion 2''a-1 are stacked one on top of the other, and are sequentially stacked and welded in the same manner to form the so-called tube body 1. Note that at the time of this welding, hardening has begun. In some cases, the welded portion may be softened again by blowing hot air using a hot air blowing device or the like.

(Effects of the Invention) As explained above, in the synthetic resin pipe manufactured by the apparatus of the present invention, the outer spiral protrusion is formed of hard synthetic resin, and the inner wall is formed of soft synthetic resin. Because it has high flat strength, flexibility, and flat inner walls, it is easy to insert electric wires into the pipe, for example, or when used as a drainage pipe, its flow resistance is extremely low. Therefore, such synthetic resin pipes can be manufactured continuously and easily using a manufacturing apparatus having an extremely simple structure, and the manufacturing cost can be significantly reduced.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention, and FIG. 1 is a plan view thereof, FIG. 2 is a longitudinal sectional view thereof, FIG. 3 is a sectional view taken along the line of FIG. 2, and FIG. 5 is a sectional view taken along a line taken from FIG. 3, FIG. 6 is a partially omitted cross sectional view of a molding die, FIG. 9 is a front view of a synthetic resin pipe manufactured by the apparatus of the present invention, and FIG. 10 is a partially enlarged sectional view thereof. DESCRIPTION OF SYMBOLS 1... Pipe body, 1a... Strip material, 2a... U-shaped part, 2a-1... Narrow plate-shaped part, 3a... Wide plate-shaped part, 11... Main shaft for forming, 23... Metal for forming type,
23a...first passage, 23b...second passage.

Claims (1)

[Claims] 1. A molding die is provided for supplying a synthetic resin strip material to a molding main shaft, and a U-shaped part with narrow plate-shaped parts on both side edges is molded in the mold using a semi-molten hard synthetic resin. A first passage and a second passage for molding the wide plate-like part with semi-molten soft synthetic resin are formed, and the molding passage part of the narrow plate-like part on one side in the first passage and the wide plate-like part in the second passage are formed. A molded passage portion on one side edge of the plate-shaped portion is formed to communicate with the molded passage portion in front of the outlet to form a common passage portion, and a U-shaped portion and a narrow plate-shaped portion extending from one side of the opening edge of the U-shaped portion, and A strip material having a cross-sectional shape with a wide plate-like part extending from the other side of the opening edge, in which the U-shaped part and the narrow plate-like part are made of hard synthetic resin, and the wide plate-like part is made of soft synthetic resin, is molded and supplied. 1. A synthetic resin pipe manufacturing device characterized in that it is configured as follows.